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.The Windows Registry is a hierarchical database that stores configuration settings and options on Microsoft Windows operating systems.^ Registry is a database where Windows and programs store their data.
  • Windows Registry Software - Registry Rinse, Max Secure Registry Cleaner, Registry Clean Pro ... 18 January 2010 4:17 UTC www.filetransit.com [Source type: FILTERED WITH BAYES]
  • Windows Nt Registry Software Free Download 18 January 2010 4:17 UTC top.softlandmark.com [Source type: General]
  • Windows Me Registry Software Free Download 18 January 2010 4:17 UTC top.softlandmark.com [Source type: General]
  • Registry Repair Software - EASY REGISTRY, Migo Registry Repair, Windows Registry Repair Pro ... 18 January 2010 4:17 UTC www.filetransit.com [Source type: General]

^ The Windows Registry is a grouped database storing all of the Window’s Operating System settings, preferences, and hardware configurations.
  • Your Windows Registry Explained | Spyware Techie 18 January 2010 4:17 UTC www.spyware-techie.com [Source type: General]

^ The registry is a large and complex database, even before installing any third party software The Windows Registry is a database for storing program settings and options for Windows operating systems.

.It contains settings for low-level operating system components as well as the applications running on the platform: the kernel, device drivers, services, SAM, user interface and third party applications all make use of the Registry.^ Applications and drivers being added to the system .
  • Registry Cleaner from RegistryOptimizer.com 18 January 2010 4:17 UTC www.registryoptimizer.com [Source type: FILTERED WITH BAYES]

^ Users making changes to the Registry database .
  • Registry Cleaner from RegistryOptimizer.com 18 January 2010 4:17 UTC www.registryoptimizer.com [Source type: FILTERED WITH BAYES]

^ A given application typically has dozens of settings strewn all over the registry.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.The registry also provides a means to access counters for profiling system performance.^ Provides for top notch system performance.

^ Hence, it is necessary to be well aware of the reasons behind the poor performance of your system and the means of rectifying the same.
  • Windows xp registry cleaner|registry cleaner software download|Download Now-download-registry-cleaners.com | 18 January 2010 4:17 UTC www.download-registry-cleaners.com [Source type: General]

^ Learn more about Windows Registry Guide 2003 (Download doesn't provide access to previous versions of this program.
  • Windows Registry Guide 2002 - Free Mobile software downloads and software reviews - CNET Download.com 18 January 2010 4:17 UTC download.cnet.com [Source type: General]

.When first introduced with Windows 3.1, the Windows registry's primary purpose was to store configuration information for COM-based components.^ Windows registry information for advanced users .
  • Windows registry information for advanced users 18 January 2010 4:17 UTC support.microsoft.com [Source type: Reference]

^ The Windows Registry is a database repository for information about a computer's configuration.
  • Free Windows Registry Download at Shareware Update 18 January 2010 4:17 UTC www.sharewareupdate.com [Source type: General]
  • Windows Me Registry - Registry Rinse, Registry File Repair, Free Window Registry Repair - and Others 18 January 2010 4:17 UTC shareme.com [Source type: General]
  • Windows Nt Registry Software Free Download 18 January 2010 4:17 UTC top.softlandmark.com [Source type: General]
  • Windows Me Registry Software Free Download 18 January 2010 4:17 UTC top.softlandmark.com [Source type: General]

^ Windows NT stores all its configuration information in a hierarchical database called the Registry.

.With the introduction of Windows 95 and Windows NT, its use was extended to tidy up the profusion of per-program INI files that had previously been used to store configuration settings for Windows programs.^ INI files were small text documents that stored all the program settings and configurations, and one could use Notepad to edit them.

^ Sort of like a Windows 3.1 INI file.
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

^ With the use of this software it's possible to remove the Windows Installer configuration of a program if it ...
  • Download windows registry repair 18 January 2010 4:17 UTC downloads.phpnuke.org [Source type: General]
  • Download windows xp registry cleaner 18 January 2010 4:17 UTC downloads.phpnuke.org [Source type: General]

[1]

Contents

Structure

Keys and values

.The registry contains two basic elements: keys and values.^ What are registry hives, registry keys and registry values?

^ A key can contain sub keys and value entries.
  • Windows Registry Access in VB.NET 18 January 2010 4:17 UTC it.toolbox.com [Source type: Reference]

^ The registry contains two basic elements: keys and values.
  • Knowing the Windows Registry | Cleaner Registry | Top Cleaner - Registry Fix 18 January 2010 4:17 UTC cleanerregistryfix.com [Source type: General]

.Registry Keys are similar to folders - in addition to values, each key can contain subkeys, which may contain further subkeys, and so on.^ What are registry hives, registry keys and registry values?

^ Subkeys may contain further subkeys.

^ The registry contains two basic elements: keys and values.
  • Knowing the Windows Registry | Cleaner Registry | Top Cleaner - Registry Fix 18 January 2010 4:17 UTC cleanerregistryfix.com [Source type: General]

.Keys are referenced with a syntax similar to Windows' path names, using backslashes to indicate levels of hierarchy.^ The keys are very similar to folders in that they are referenced with syntaxes and backslashes which are used to indicate the different levels of hierarchy.

^ Entries are referenced by their registry path and name.
  • Overview of the Windows Registry: Core Services 18 January 2010 4:17 UTC technet.microsoft.com [Source type: Reference]

^ You can use context menu to navigate to referenced key, open containing folder or open URL if the key or value contains a ProgID, ClassID, folder, file path or URL. Allow to open multiple local registry windows.
  • Windows Registry Editor - Restore Registry Edit Backup Registry 18 January 2010 4:17 UTC www.tomdownload.com [Source type: General]

E.g. .HKEY_LOCAL_MACHINE\Software\Microsoft\Windows refers to the subkey "Windows" of the subkey "Microsoft" of the subkey "Software" of the HKEY_LOCAL_MACHINE key.^ HKEY_CURRENT_CONFIG is an example of Registry Hive HKEY_LOCAL_MACHINE\Software\Microsoft\ is an example of a registry key .

^ This is what the key should look like HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon shell = Explorer.exe This runs the virus/parasite of your (actually, their) choice HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon shell = Explorer.exe C:\WINDOWS\Any_Virus_You_Want.exe What happens is that Explorer.exe is the program that displays the desktop (also known as the shell ).
  • The Windows 9x Registry 18 January 2010 4:17 UTC mc-computing.com [Source type: FILTERED WITH BAYES]

^ The HKEY_LOCAL_MACHINE\HARDWARE key is a dynamic subkey that is generated every time Windows NT is booted by the NT hardware recognizer ( NTDETECT.COM ) and the NT kernel.

There are six Root Keys:
  • HKEY_CLASSES_ROOT
  • HKEY_CURRENT_USER
  • HKEY_LOCAL_MACHINE
  • HKEY_USERS
  • HKEY_CURRENT_CONFIG
  • HKEY_DYN_DATA
.Registry Values are name/data pairs stored within keys.^ What are registry hives, registry keys and registry values?

^ Each Registry value is stored as one of five data types: .

^ Note that case matters when typing Registry key names and values.
  • Understanding the Windows 9x Registry: Part II. 18 January 2010 4:17 UTC www.geekgirls.com [Source type: FILTERED WITH BAYES]

.Values are referenced separately from keys.^ You can use the -K option to provide an alternate key/value separator character.

^ When name is an empty string ( "" ), the key's default value is referenced.
  • registry -- display and modify the Windows Registry Database 18 January 2010 4:17 UTC www.mkssoftware.com [Source type: Reference]

^ By default, the last "\" or "/" is assumed to be the separator between the key and the value.

.Value names can contain backslashes but doing so makes them difficult to distinguish from their key paths.^ A key can contain sub keys and value entries.
  • Windows Registry Access in VB.NET 18 January 2010 4:17 UTC it.toolbox.com [Source type: Reference]

^ String values contain paths to executable that are executed based on the rules of the key.
  • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

^ Each key can contain other keys, as well as Values .

.The Windows API functions that query and manipulate registry values take value names separately from the key path and/or handle that identifies the parent key.^ What are registry hives, registry keys and registry values?

^ System Key” stands for the location of a Windows registry value.
  • » Make Users Log Into Windows » 411 on Registry Tweaks & Repair 18 January 2010 4:17 UTC www.411-registry-repair.com [Source type: General]

^ The program specifies an entry by its path and name, and the API returns the value of the entry.
  • Overview of the Windows Registry: Core Services 18 January 2010 4:17 UTC technet.microsoft.com [Source type: Reference]

.The terminology is somewhat misleading, as the values are similar to an associative array, where standard terminology would refer to the name part of the value as a "key". The terms are a holdout from the 16-bit registry in Windows 3, in which keys could not contain arbitrary name/data pairs, but rather contained only one unnamed value (which had to be a string).^ What are registry hives, registry keys and registry values?

^ A key can contain sub keys and value entries.
  • Windows Registry Access in VB.NET 18 January 2010 4:17 UTC it.toolbox.com [Source type: Reference]

^ Each key can contain other keys (sometimes referred to as sub-keys), as well as Values.
  • All about Windows Registry 18 January 2010 4:17 UTC www.registryrid.com [Source type: Reference]
  • The Windows Registry 18 January 2010 4:17 UTC www.go4expert.com [Source type: FILTERED WITH BAYES]

.In this sense, the entire registry was like an associative array where the keys (in both the registry sense and dictionary sense) formed a hierarchy, and the values were all strings.^ What are registry hives, registry keys and registry values?

^ Delete these keys or values from the registry.
  • Registry key for Windows Explorer Views. - Configuration-Customize - Windows-XP 18 January 2010 4:17 UTC www.tomshardware.com [Source type: FILTERED WITH BAYES]

^ Registry keys can be empty - they have no associated value.

.When the 32-bit registry was created, so was the additional capability of creating multiple named values per key, and the meanings of the names were somewhat distorted.^ What are registry hives, registry keys and registry values?

^ Create the a Dword value and name it "ProtectionMode " 4.

^ Note that case matters when typing Registry key names and values.
  • Understanding the Windows 9x Registry: Part II. 18 January 2010 4:17 UTC www.geekgirls.com [Source type: FILTERED WITH BAYES]

[2]
There are a number of different types of values:
List of Registry Value Types
0 REG_NONE No type
1 REG_SZ A string value
2 REG_EXPAND_SZ An "expandable" string value that can contain environment variables
3 REG_BINARY Binary data (any arbitrary data)
4 REG_DWORD / REG_DWORD_LITTLE_ENDIAN A DWORD value, a 32-bit unsigned integer (numbers between 0 and 4,294,967,295 [232 – 1]) (little-endian)
5 REG_DWORD_BIG_ENDIAN A DWORD value, a 32-bit unsigned integer (numbers between 0 and 4,294,967,295 [232 – 1]) (big-endian)
6 REG_LINK symbolic link (UNICODE)
7 REG_MULTI_SZ A multi-string value, which is an array of unique strings
8 REG_RESOURCE_LIST Resource list
9 REG_FULL_RESOURCE_DESCRIPTOR Resource descriptor
10 REG_RESOURCE_REQUIREMENTS_LIST Resource Requirements List
11 REG_QWORD / REG_QWORD_LITTLE_ENDIAN A QWORD value, a 64-bit integer (either big- or little-endian, or unspecified) (Introduced in Windows 2000)

Hives

.The Registry is split into a number of logical sections, or "hives"[3] (the reason the word hive was used is an in-joke).^ The entire registry is split into logical sections that are called hives .
  • Working with the Windows Registry in C++ 18 January 2010 4:17 UTC www.aspfree.com [Source type: FILTERED WITH BAYES]

^ Registry Hives The windows registry is divided into a number of hives.

^ HIVES (main registry folders) and their use The registry is split into a number of logical sections named "hives", those are the top main folder that can added, edited or renamed.
  • What is Windows registry (Registry Keys) - a knol by Omar Abid 18 January 2010 4:17 UTC knol.google.com [Source type: FILTERED WITH BAYES]

[4] .Hives are generally named by their Windows API definitions, which all begin "HKEY". They are abbreviated to a three- or four-letter short name starting with "HK" (e.g.^ They all start with "HKEY" prefix.
  • What is Windows registry (Registry Keys) - a knol by Omar Abid 18 January 2010 4:17 UTC knol.google.com [Source type: FILTERED WITH BAYES]

^ MMM - Month as a three-letter abbreviation.
  • Messenger Plus! Live - Registry Settings 18 January 2010 4:17 UTC www.msgpluslive.net [Source type: FILTERED WITH BAYES]

^ Day of week as a three-letter abbreviation.
  • Messenger Plus! Live - Registry Settings 18 January 2010 4:17 UTC www.msgpluslive.net [Source type: FILTERED WITH BAYES]

HKCU and HKLM).
.The HKEY_LOCAL_MACHINE (local machine-specific configuration data) and HKEY_CURRENT_USER (user-specific configuration data) nodes have a similar structure to each other; user applications typically look up their settings by first checking for them in "HKEY_CURRENT_USER\Software\Vendor's name\Application's name\Version\Setting name", and if the setting is not found, look instead in the same location under the HKEY_LOCAL_MACHINE key[citation needed].^ Roaming is for non-machine specific settings that will follow the user.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ Usually, though, it will be safe to restore the application's user settings from the HKEY_CURRENT_USER\Software branch.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ The HKEY_LOCAL_MACHINE\Software\Classes key contains default settings that can apply to all users on the local computer.
  • Windows registry information for advanced users 18 January 2010 4:17 UTC support.microsoft.com [Source type: Reference]

.However, the converse may apply for administrator-enforced policy settings where HKLM may take precedence over HKCU. The Windows Logo Program has specific requirements for where different types of user data may be stored, and that the concept of least privilege be followed so that administrator-level access is not required to use an application.^ Registry is a database where Windows and programs store their data.
  • Windows Registry Software - Registry Rinse, Max Secure Registry Cleaner, Registry Clean Pro ... 18 January 2010 4:17 UTC www.filetransit.com [Source type: FILTERED WITH BAYES]
  • Windows Nt Registry Software Free Download 18 January 2010 4:17 UTC top.softlandmark.com [Source type: General]
  • Windows Me Registry Software Free Download 18 January 2010 4:17 UTC top.softlandmark.com [Source type: General]
  • Registry Repair Software - EASY REGISTRY, Migo Registry Repair, Windows Registry Repair Pro ... 18 January 2010 4:17 UTC www.filetransit.com [Source type: General]

^ Windows applications store their settings and information using the combination of Registry keys and values.

^ The following table lists the data types currently used by the system.

[Note 1][5]

HKEY_CLASSES_ROOT (HKCR)

.Abbreviated HKCR, HKEY_CLASSES_ROOT stores information about registered applications, such as file associations and OLE Object Class IDs, tying them to the applications used to handle these items.^ HKEY_CLASSES_ROOT Stores information about registered applications, such as Associations from File Extensions and OLE Object Class ID's tying them to the applications used to handle these items.
  • What is Windows registry (Registry Keys) - a knol by Omar Abid 18 January 2010 4:17 UTC knol.google.com [Source type: FILTERED WITH BAYES]

^ It contains information on files associations (matching a file extension to an application), as well as acts as the repository for OLE classes.

^ HKEY_CLASSES_ROOT (HKCR) : Contains file extension associations and COM class registration information.
  • Optimizing the Windows Registry, the Registry Editor, registry tweaks and tracking changes to the registry. 18 January 2010 4:17 UTC www.optimizingpc.com [Source type: FILTERED WITH BAYES]

.On Windows 2000 and above, HKCR is a compilation of user-based HKCU\Software\Classes and machine-based HKLM\Software\Classes.^ HKCR is a combination of the sub keys HKLM\SOFTWARE\Classes and HKCU\SOFTWARE\Classes .
  • Optimizing the Windows Registry, the Registry Editor, registry tweaks and tracking changes to the registry. 18 January 2010 4:17 UTC www.optimizingpc.com [Source type: FILTERED WITH BAYES]

^ On Windows-NT based systems such as Windows NT, 2000, XP and Vista, each user’s settings are stored in their own files called NTUSER.DAT and USRCLASS.DAT inside their own Documents and Settings subfolder (or their own Users subfolder in Windows Vista).
  • How To Edit Windows Registry Key Values without Booting in Windows » Raymond.CC Blog 18 January 2010 4:17 UTC www.raymond.cc [Source type: General]

^ When querying these or other items from HKLM (or HKU, where user account and related information is stored), use the reg command against a remote Windows machine across the network with Windows Server Message Block (SMB) connections.
  • Windows registry forensics: Investigating system-wide settings 18 January 2010 4:17 UTC searchsecurity.techtarget.com [Source type: FILTERED WITH BAYES]

.If a given value exists in both of the subkeys above, the one in HKCU\Software\Classes takes precedence.^ Fonts is a subkey under software and has values.
  • Working with Windows Registry using VB.NET - CodeProject 18 January 2010 4:17 UTC www.codeproject.com [Source type: FILTERED WITH BAYES]

^ The command syntax for such a comparison follows: reg compare "HKU\.Default\Control Panel\Desktop" "HKCU\Control Panel\Desktop" /s /od The /s option tells CompReg to check subkeys and values that exist under each key specified.
  • Windows Registry / Recommended P 18 January 2010 4:17 UTC www.softpanorama.org [Source type: FILTERED WITH BAYES]

^ HKCR is a combination of the sub keys HKLM\SOFTWARE\Classes and HKCU\SOFTWARE\Classes .
  • Optimizing the Windows Registry, the Registry Editor, registry tweaks and tracking changes to the registry. 18 January 2010 4:17 UTC www.optimizingpc.com [Source type: FILTERED WITH BAYES]

[6] .The design allows for either machine- or user-specific registration of COM objects.^ When an application attempts to register a COM object, the WOW64 emulator will place the registration in the appropriate section of the registry, depending on whether the COM object is a 64-bit or 32-bit object.

^ Roaming is for non-machine specific settings that will follow the user.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ And your apps don't work on multi-user machines, either.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.The user-specific classes hive, unlike the HKCU hive, does not form part of a roaming user profile.^ The HKEY_CURRENT_USER hive roams with the user's profile, making it portable.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ Roaming is for non-machine specific settings that will follow the user.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ The user account specific settings ( HKCU ) are stored in the file NTUSER.DAT in the personal folder (XP: C:\Documents and Settings\ loginname , Vista: C:\Users\ loginname ).
  • Optimizing the Windows Registry, the Registry Editor, registry tweaks and tracking changes to the registry. 18 January 2010 4:17 UTC www.optimizingpc.com [Source type: FILTERED WITH BAYES]

HKEY_CURRENT_USER (HKCU)

.Abbreviated HKCU, HKEY_CURRENT_USER stores settings that are specific to the currently logged-in user.^ Hkey_Current_User contains the database with the user profile of the user who is currently logged on.

^ HKEY_CURRENT_USER (HKCU) : Contains the preferences of the current user (user level settings).
  • Optimizing the Windows Registry, the Registry Editor, registry tweaks and tracking changes to the registry. 18 January 2010 4:17 UTC www.optimizingpc.com [Source type: FILTERED WITH BAYES]

^ It contains individual user settings for the user who is currently logged on, e.g.

[7] .The HKCU key is a link to the subkey of HKEY_USERS that corresponds to the user; the same information is accessible in both locations.^ HKEY_CLASSES_ROOT= HKCR HKEY_CURRENT_USER= HKCU HKEY_LOCAL_MACHINE= HKLM HKEY_CURRENT_CONFIG= HKCC HKEY_USERS= HKU Other subsidiary keys branch off of these root keys.
  • Warp Speed! - Tweaking The Windows Registry 18 January 2010 4:17 UTC www.toejumper.net [Source type: FILTERED WITH BAYES]

^ Windows Registry indeed standardized both the format and the location required by information storage needed for almost every Windows application.

^ This key points to a branch of Hkey_Users for the user who is currently logged on.

.On Windows-NT based systems, each user's settings are stored in their own files called NTUSER.DAT and USRCLASS.DAT inside their own Documents and Settings subfolder (or their own Users subfolder in Windows Vista).^ Changes made to this data are written to a USER.DAT file stored in the user's subfolder of the Windows Profiles folder.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ File association fixes for Windows Vista .
  • Windows XP Fixes, Tips and Tweaks 18 January 2010 4:17 UTC windowsxp.mvps.org [Source type: FILTERED WITH BAYES]

^ System settings are stored in %systemroot%\system32\config\systemprofile in NTUSER.DAT and UsrClass.dat - read only for standard users/LUAs .
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.Settings in this hive follow users with a roaming profile from machine to machine.^ Roaming is for non-machine specific settings that will follow the user.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ The HKEY_CURRENT_USER hive roams with the user's profile, making it portable.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ Registry can be compared with a file system but instead of folders and files it contains individual Windows settings, user settings and hardware profiles.

HKEY_LOCAL_MACHINE (HKLM)

.Abbreviated HKLM, HKEY_LOCAL_MACHINE stores settings that are specific to the local computer.^ Most settings on our computers are stored in the registry somewhere, we just need to know what to change to achieve what we want.
  • How-to: Hack your Windows Mobile registry « Inspect My Gadget 18 January 2010 4:17 UTC www.inspectmygadget.com [Source type: General]

^ The various Hkey_Local_Machine \Software Description subkeys contain the names and version numbers of the software installed on the local computer (if that software writes information to the Registry as part of its installation process).

^ HKLM\SOFTWARE\HTC\Camera\Video\SaveFolder The folder you specify here is inside My Documents, i.e., if you set the value "Pictures" it will store them in "\My Documents\Pictures".
  • Windows Mobile 5 Registry Tweaks - MoDaCo 18 January 2010 4:17 UTC wiki.modaco.com [Source type: FILTERED WITH BAYES]

[8] .On NT-based versions of Windows, HKLM contains four subkeys, SAM, SECURITY, SOFTWARE and SYSTEM, that are found within their respective files located in the %SystemRoot%\System32\config folder.^ All versions of the Windows Operating System contain what is called the Windows Registry.

^ Windows Me also contains a classes.dat file in addition to the user and system dat files.
  • The Windows Registry 18 January 2010 4:17 UTC www.go4expert.com [Source type: FILTERED WITH BAYES]
  • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

^ You will need to located this file (typically located in the %SYSTEMROOT%\SYSTEM32 folder).
  • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

.A fifth subkey, HARDWARE, is volatile and is created dynamically, and as such is not stored in a file.^ The Windows registry, stored on your PC in several files, records the relationship between hardware, memory space, and addressing.
  • Solve All your Windows Errors Today! Free Download of Registry Cleaning Software 18 January 2010 4:17 UTC localpesthelp.com [Source type: General]

^ For all types of devices, subkeys contain information such as device type, assigned drive letter, hardware ID, and device manufacturer, plus driver-related information for network components.

^ If an application supports Dynamic Data Exchange (DDE), the Shell subkey can contain Open and Print subkeys that define DDE commands for opening and printing files, similar to the OLE and DDE information stored in the Registry under earlier versions of Windows.

.Information about system hardware drivers and services are located under the SYSTEM subkey, while the SOFTWARE subkey contains software and Windows settings.^ Subkeys containing Control Panel settings, including information stored in WIN.INI and CONTROL.INI under Windows 3.x .

^ Containing information and settings for all the hardware, software, users, and preferences of your computer.
  • Solve All your Windows Errors Today! Free Download of Registry Cleaning Software 18 January 2010 4:17 UTC localpesthelp.com [Source type: General]

^ Contains information about the hardware profile used by the local computer at system startup.
  • Working with Windows Registry using VB.NET - CodeProject 18 January 2010 4:17 UTC www.codeproject.com [Source type: FILTERED WITH BAYES]

HKEY_USERS (HKU)

.Abbreviated HKU, HKEY_USERS contains subkeys corresponding to the HKEY_CURRENT_USER keys for each user profile actively loaded on the machine, though user hives are usually only loaded for currently logged-in users.^ Hkey_Current_User contains the database with the user profile of the user who is currently logged on.

^ HKEY_CURRENT_USER - this branch points to the part of HKEY_USERS appropriate for the current user.
  • Windows Registry / Recommended P 18 January 2010 4:17 UTC www.softpanorama.org [Source type: FILTERED WITH BAYES]

^ HKEY_CURRENT_USER (HKCU) : Contains the preferences of the current user (user level settings).
  • Optimizing the Windows Registry, the Registry Editor, registry tweaks and tracking changes to the registry. 18 January 2010 4:17 UTC www.optimizingpc.com [Source type: FILTERED WITH BAYES]

HKEY_CURRENT_CONFIG

.Abbreviated HKCC, HKEY_CURRENT_CONFIG contains information gathered at runtime; information stored in this key is not permanently stored on disk, but rather regenerated at the boot time.^ HKEY_CLASSES_ROOT= HKCR HKEY_CURRENT_USER= HKCU HKEY_LOCAL_MACHINE= HKLM HKEY_CURRENT_CONFIG= HKCC HKEY_USERS= HKU Other subsidiary keys branch off of these root keys.
  • Warp Speed! - Tweaking The Windows Registry 18 January 2010 4:17 UTC www.toejumper.net [Source type: FILTERED WITH BAYES]

^ The HKEY_LOCAL_MACHINE\HARDWARE key is a dynamic subkey that is generated every time Windows NT is booted by the NT hardware recognizer ( NTDETECT.COM ) and the NT kernel.

^ HKEY_CURRENT_CONFIG (HKCC) : The information in this key is used for the chosen hardware profile (in most cases there is only one available) and stores similar information to the sub key HKLM\SYSTEM\CurrentControlSet\Hardware Profiles\Current .
  • Optimizing the Windows Registry, the Registry Editor, registry tweaks and tracking changes to the registry. 18 January 2010 4:17 UTC www.optimizingpc.com [Source type: FILTERED WITH BAYES]

.It is a link to HKEY_LOCAL_MACHINE\System\CurrentControlSet\Hardware Profiles\Current.^ The sixth handle is the current config handle, and it is just a pointer to HKLM\System\CurrentControlSet\Hardware Profiles , and it should only exist in Windows NT4, 2000 and XP. So if you updated the current config hive it would actually update the items under the hardware profiles key.
  • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

^ All the profiles are stored in separate branches under HKEY_LOCAL_MACHINE and HKEY_CURRENT_CONFIG provides a direct route to the current one.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ (Windows 9X)You can set DefaultRcvWindow, and DefaultTTL by adding these string values to HKEY_LOCAL_MACHINE\ System\ CurrentControlset\ Services\ VXD\ MSTCP Set the DefaultRcvWindow to"5840"and the DefaultTTL to "128" .

HKEY_PERFORMANCE_DATA

.This key provides runtime information into performance data provided by either the NT kernel itself or other programs that provide performance data.^ The HKEY_LOCAL_MACHINE\HARDWARE key is a dynamic subkey that is generated every time Windows NT is booted by the NT hardware recognizer ( NTDETECT.COM ) and the NT kernel.

^ The Registry holds information about default data and auxiliary file locations, menus, button bars, window status, and other options.
  • Registry Cleaner from RegistryOptimizer.com 18 January 2010 4:17 UTC www.registryoptimizer.com [Source type: FILTERED WITH BAYES]

^ USB drive & iPod history Beyond these autostart keys, the registry also remembers information about every USB token ever plugged into the system.
  • Windows registry forensics: Investigating system-wide settings 18 January 2010 4:17 UTC searchsecurity.techtarget.com [Source type: FILTERED WITH BAYES]

This key is not displayed in the Registry Editor, but it is visible through the registry functions in the Windows API.

HKEY_DYN_DATA

.This key is used only on Windows 95, Windows 98 and Windows Me.^ Only Windows 95 and Windows 98.

^ As mentioned before, after using your PC for a while, the Windows Registry accumulates keys and values that are no longer in use.

^ By using Registry Fix 3.0 regularly and fixing your Registry , your system will not only be more stable but will also help Windows and your software run faster.
  • Windows Me Registry - Registry Rinse, Registry File Repair, Free Window Registry Repair - and Others 18 January 2010 4:17 UTC shareme.com [Source type: General]

[9] .It contains information about hardware devices, including Plug and Play and network performance statistics.^ Plug and Play devices on an ISA bus .

^ Information about hardware devices on the system .

^ Hardware devices can place information in the Registry automatically using the Plug and Play interface.

.The information in this hive is also not stored on the hard drive.^ The best place to store the backups is on a mobile hard drive or burn them onto a CD/DVD so that they wont be lost even if Windows is corrupted.

^ The 'System Volume Information' Folder What is it and why is it taking up room on your hard drive(s)?
  • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

^ It is also recommended that you store the Registry backup files on a separate location than your main hard drive.

.The Plug and Play information is gathered and configured at startup and is stored in memory.^ It is used for storing computer configuration information into memory.
  • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

^ Each time you add or remove a Plug and Play-compliant device on a computer running Windows 95, configuration data is added to the Registry.

^ Windows NT stores all its configuration information in a hierarchical database called the Registry.

[10]

Aliases

Aliases in the Windows 9x registry:
Root key Aliases for
HKEY_CLASSES_ROOT HKEY_LOCAL_MACHINE\Software\Classes
HKEY_CURRENT_USER User’s branch within HKEY_USERS
HKEY_CURRENT_CONFIG Hardware profile within HKEY_LOCAL_MACHINE\Config

Editing

Manual editing

The Registry Editor in Windows Vista
Windows 3.11 Registry Editor
.The registry can be edited manually in Microsoft Windows by running regedit.exe or regedt32.exe in the Windows directory.^ Microsoft/Description of the Microsoft Windows registry .

^ Description of the Microsoft Windows registry .

^ Windows boxes: the "Run" registry keys.
  • Windows registry forensics: Investigating system-wide settings 18 January 2010 4:17 UTC searchsecurity.techtarget.com [Source type: FILTERED WITH BAYES]

.However, careless registry editing can cause irreversible damage.^ However with the current tools out there, you're just as likely to cause some damage as well so it's sort of like a catch-22.
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

^ NOTE: incorrectly editing Windows Registry may damages your system registry entries, before editing create a restore point.
  • Registry Tweaks For Windows Xp - Part 2 18 January 2010 4:17 UTC www.trap17.com [Source type: FILTERED WITH BAYES]

^ However, editing the registry may sometimes be the best method to resolve a product issue.
  • Windows registry information for advanced users 18 January 2010 4:17 UTC support.microsoft.com [Source type: Reference]

.Thus, performing backups of the registry before editing it is highly recommended by Microsoft and many industry experts (such as the authors and editors of leading trade magazines).^ It is strongly recommended that you backup your Registry before editing.
  • SpeedGuide.net :: Windows 2k/XP Registry Tweaks 18 January 2010 4:17 UTC www.speedguide.net [Source type: FILTERED WITH BAYES]

^ It's critical that before you do any editing you make a backup of the current registry.
  • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

^ If the issue is documented in the Microsoft Knowledge Base, an article with step-by-step instructions to edit the registry for that issue will be available.
  • Windows registry information for advanced users 18 January 2010 4:17 UTC support.microsoft.com [Source type: Reference]

.A simple implementation of the current registry tool appeared in Windows 3.x, called the "Registration Info Editor" or "Registration Editor". This was basically just a database of applications used to edit embedded OLE objects in documents.^ You can use the Console Registry Tool for Windows (Reg.exe) to edit the registry.
  • Windows registry information for advanced users 18 January 2010 4:17 UTC support.microsoft.com [Source type: Reference]

^ Reg is a command-line tool called the Console Registry Tool for Windows.

^ It is called, surprisingly enough, the Registry Editor.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

.Windows 9x operating systems include REGEDIT.EXE which can be used in Windows and also in real mode MS-DOS.^ Its filename is REGEDIT.EXE under Windows 9x and REGEDT32.EXE under Windows NT. .
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ As you can see, this key is part of HKEY_CURRENT_USER and not the system-wide HKEY_LOCAL_MACHINE. Programs that use this mechanism run when the user logs in (or when the default desktop loads if user profiles aren't enabled under Windows 9x.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ By using Registry Fix 3.0 regularly and fixing your Registry , your system will not only be more stable but will also help Windows and your software run faster.
  • Windows Me Registry - Registry Rinse, Registry File Repair, Free Window Registry Repair - and Others 18 January 2010 4:17 UTC shareme.com [Source type: General]

[11] .Windows NT introduced permissions for Registry editing.^ Microsoft introduced the Windows Registry in Windows95.

^ You can use the Console Registry Tool for Windows (Reg.exe) to edit the registry.
  • Windows registry information for advanced users 18 January 2010 4:17 UTC support.microsoft.com [Source type: Reference]

^ To answer this question, you must first look at several common reasons for editing the Windows registry.

.Windows NT 4.0 and Windows 2000 were distributed with both the Windows 9x REGEDIT.EXE program and Windows NT 3.x's REGEDT32.EXE program.^ Its filename is REGEDIT.EXE under Windows 9x and REGEDT32.EXE under Windows NT. .
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ An alternative Registry Editor (REGEDT32.EXE) is available for use with Windows NT/2000, it includes some additional features not found in the standard version, including; the ability to view and modify security permissions, and being able to create and modify the extended string values REG_EXPAND_SZ & REG_MULTI_SZ. .

^ A Windows 98 computer may only have one user, but Windows NT/2000 supports multiple users and insists that you log on to the system to use it.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

There are several differences between the two editors on these platforms:
.
  • REGEDIT.EXE has a left-side tree view that begins at "My Computer" and lists all loaded hives.^ As briefly mentioned before, the program Regedit.Exe included with Windows enables you to view, search and edit the data within the Registry.

    ^ The left-hand pane contains a collapsible tree view of the key hierarchy.
    • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

    ^ Ed July 2nd, 2008 at 11:22 pm 4 If you chose the program RegEdit(remote), this is the next line on the menu, it will auto load the hives .
    • How To Edit Windows Registry Key Values without Booting in Windows » Raymond.CC Blog 18 January 2010 4:17 UTC www.raymond.cc [Source type: General]

    .REGEDT32.EXE has a left-side tree view, but each hive has its own window, so the tree displays only keys.
  • REGEDIT.EXE represents the three components of a value (its name, type, and data) as separate columns of a table.^ Each value entry has a data type and value .

    ^ Note that case matters when typing Registry key names and values.
    • Understanding the Windows 9x Registry: Part II. 18 January 2010 4:17 UTC www.geekgirls.com [Source type: FILTERED WITH BAYES]

    ^ The value names are the font name as it is displayed, and the value data is the filename (and path if the font file is not in \Windows\Fonts).
    • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

    .REGEDT32.EXE represents them as a list of strings.
  • REGEDIT.EXE supports right-clicking of entries in a tree view to adjust properties and other settings.^ If a red circled X appears to the left of any such entry, you can click the View Details link to see what the program has discovered.
    • Clean The Windows Registry To Keep PCs Lean & Mean - Custom Systems/White Box - IT Channel News by CRN 18 January 2010 4:17 UTC www.crn.com [Source type: General]

    ^ Double-click Userinit and set it’s value correctly such as C:\Windows\System32\Userinit.exe, Important Note: Make sure you include the comma at the end after Userinit.exe.
    • How To Edit Windows Registry Key Values without Booting in Windows » Raymond.CC Blog 18 January 2010 4:17 UTC www.raymond.cc [Source type: General]

    ^ Look for Userinit key and make sure that the value is set as C:\Windows\System32\Userinit.exe, If the Userinit key is not there, you can add a new key by right clicking at the right pane and select Add Key.
    • How To Edit Windows Registry Key Values without Booting in Windows » Raymond.CC Blog 18 January 2010 4:17 UTC www.raymond.cc [Source type: General]

    .REGEDT32.EXE requires all actions to be performed from the top menu bar.
  • REGEDIT.EXE supports searching for key names, values, or data throughout the entire registry, whereas REGEDT32.EXE only supports searching for key names in one hive at a time.
  • Because REGEDIT.EXE was directly ported from Windows 95, it does not support editing permissions.^ It will search the Windows Registry for unnecessary Registry keys and fix Registry errors.
    • Windows Me Registry - Registry Rinse, Registry File Repair, Free Window Registry Repair - and Others 18 January 2010 4:17 UTC shareme.com [Source type: General]

    ^ Its filename is REGEDIT.EXE under Windows 9x and REGEDT32.EXE under Windows NT. .
    • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

    ^ Instead, the values of a key inherit the permissions of the key.
    • The Windows Registry 18 January 2010 4:17 UTC www.go4expert.com [Source type: FILTERED WITH BAYES]
    • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

    (Permissions do not exist on Windows 9x). .Therefore, of the two, only REGEDT32.EXE can access the full functionality of an NT registry.
  • REGEDIT.EXE only supports string (REG_SZ), binary (REG_BINARY), and DWORD (REG_DWORD) values.^ Registry values (string-, DWORD- and binary value) Registry values can contain different types of data.
    • Optimizing the Windows Registry, the Registry Editor, registry tweaks and tracking changes to the registry. 18 January 2010 4:17 UTC www.optimizingpc.com [Source type: FILTERED WITH BAYES]

    ^ Another value type is the binary type , or REG_BINARY .
    • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

    ^ Its filename is REGEDIT.EXE under Windows 9x and REGEDT32.EXE under Windows NT. .
    • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

    .REGEDT32.EXE supports those, plus expandable string (REG_EXPAND_SZ) and multi-string (REG_MULTI_SZ).^ An alternative Registry Editor (REGEDT32.EXE) is available for use with Windows NT/2000, it includes some additional features not found in the standard version, including; the ability to view and modify security permissions, and being able to create and modify the extended string values REG_EXPAND_SZ & REG_MULTI_SZ. .

    ^ In Windows NT4 and 2000 the information registration editor will display and allow you to edit REG_EXPAND_SZ and REG_MULTI_SZ values, but they will display those values to binary.
    • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

    ^ Another string type exists and is known as an expandable string , or REG_EXPAND_SZ .
    • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

    .Attempting to edit unsupported key types with REGEDIT.EXE on Windows 2000 or Windows NT 4.0 will result in irreversible conversion to a supported type.^ Its filename is REGEDIT.EXE under Windows 9x and REGEDT32.EXE under Windows NT. .
    • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

    ^ This value type was first introduced in Windows 2000, and then was carried over into Windows XP and Windows Longhorn.
    • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

    ^ How To Disable Keyboard - Windows XP (5) How to disable keyboard In Windows XP 1- Go to StartMenu > Run and type "regedit" and press OK to run Windows Registry Editor.
    • Registry Tweaks For Windows Xp - Part 2 18 January 2010 4:17 UTC www.trap17.com [Source type: FILTERED WITH BAYES]

    [12]
.Windows XP was the first system to integrate these two programs into one, adopting the old REGEDIT.EXE interface and adding the REGEDT32.EXE functionality.^ Using Rundll32.exe in Windows XP .
  • The Windows Registry 18 January 2010 4:17 UTC www.go4expert.com [Source type: FILTERED WITH BAYES]

^ Its filename is REGEDIT.EXE under Windows 9x and REGEDT32.EXE under Windows NT. .
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ Despite our conception of Windows as one big and complex program, it's in reality a collection of a few hundred to even a few thousand programs.

The differences listed above are not applicable on Windows XP and newer systems; REGEDIT.EXE is the improved editor, and REGEDT32.EXE is simply a stub that invokes REGEDIT.EXE.
The Registry Editor allows users to perform the following functions:
.
  • Creating, manipulating, renaming and deleting registry keys, subkeys, values and value data
  • Importing and exporting .^ What are registry hives, registry keys and registry values?

    ^ DeleteSubKey delete the subkey with its data.
    • Working with Windows Registry 18 January 2010 4:17 UTC www.c-sharpcorner.com [Source type: FILTERED WITH BAYES]

    ^ It allows you to create keys, delete keys, add values, set or change the data for a value, delete values, view the data of values, import registry settings, export registry settings, and generally just view the structure of the registry.
    • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

    REG files, exporting data in the binary hive format
  • Loading, manipulating and unloading registry hive format files (Windows NT-based systems only)
  • Setting permissions based on ACLs (Windows NT-based systems only)
  • Bookmarking user-selected registry keys as Favorites
  • Finding particular strings in key names, value names and value data
  • Remotely editing the registry on another networked computer
.It also possible to edit the registry under Linux using the open source Offline NT Password & Registry Editor to edit the files.^ It is also possible to delete Registry Keys and Values using the .REG files.

^ It's easier and safer to use this dialog box to manage the file type associations on your system, but sometimes a problem may occur for which the Registry Editor offers the only hope of a solution.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ The registry values are stored in a file with the extension .REG , which can be read with a simple text editor like Notepad .
  • Optimizing the Windows Registry, the Registry Editor, registry tweaks and tracking changes to the registry. 18 January 2010 4:17 UTC www.optimizingpc.com [Source type: FILTERED WITH BAYES]

[13]

.REG files

.REG files .(also known as Registration entries) are text-based human-readable files for storing portions of the registry.^ When the registry value which has to be changed for a certain setting is known, then the registry change can be stored in a registry file.
  • Optimizing the Windows Registry, the Registry Editor, registry tweaks and tracking changes to the registry. 18 January 2010 4:17 UTC www.optimizingpc.com [Source type: FILTERED WITH BAYES]

^ Text-files are no more nor less human readable than the registry files.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ When Unix was created long time ago (with 5MB hard disc), they chose to store config files as text files.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.On Windows 2000 and later NT-based operating systems, they contain the string Windows Registry Editor Version 5.00 at the beginning and are Unicode-based.^ They are very important to the operation of Windows, and without them the operating system will not operate.
  • The Windows Registry 18 January 2010 4:17 UTC www.go4expert.com [Source type: FILTERED WITH BAYES]

^ Securing the Windows 2000 Registry .
  • Securing the Windows 2000 Registry 18 January 2010 4:17 UTC www.windowsecurity.com [Source type: FILTERED WITH BAYES]

^ Windows Registry Editor Version 5.00 .
  • Understanding the Windows 2003 Registry 18 January 2010 4:17 UTC www.windowsnetworking.com [Source type: FILTERED WITH BAYES]
  • Ways to Crack and Disable WGA Validation Tool and WGA Notifications plus Download and Install Bypassing Genuine Windows Validate Requirement » My Digital Life 18 January 2010 4:17 UTC www.mydigitallife.info [Source type: General]

.On Windows 9x and NT 4.0 systems, they contain the string REGEDIT4 and are ANSI-based.^ On Windows-NT based systems such as Windows NT, 2000, XP and Vista, each user’s settings are stored in their own files called NTUSER.DAT and USRCLASS.DAT inside their own Documents and Settings subfolder (or their own Users subfolder in Windows Vista).
  • How To Edit Windows Registry Key Values without Booting in Windows » Raymond.CC Blog 18 January 2010 4:17 UTC www.raymond.cc [Source type: General]

^ Secure Windows 2009 a system application containing both tweaks and utilities.
  • Best free windows registry downloads. Registry Gear - Windows Registry Cleaner And Optimizer. Fix Registry Errors. Scan and clean up your registry to improve your system's performance. 18 January 2010 4:17 UTC www.freedownloadmanager.org [Source type: General]

^ The data in Hkey_Local_Machine \System is organized into control sets that contain a complete set of parameters for device drivers and services that can be loaded with Windows 95.

[14] Windows 9x format .REG files are compatible with .Windows 2000 and later NT-based systems.^ On Windows-NT based systems such as Windows NT, 2000, XP and Vista, each user’s settings are stored in their own files called NTUSER.DAT and USRCLASS.DAT inside their own Documents and Settings subfolder (or their own Users subfolder in Windows Vista).
  • How To Edit Windows Registry Key Values without Booting in Windows » Raymond.CC Blog 18 January 2010 4:17 UTC www.raymond.cc [Source type: General]

^ A Windows 98 computer may only have one user, but Windows NT/2000 supports multiple users and insists that you log on to the system to use it.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ During a Q/A session after a presentation on the registry (introduced with NT, not Windows 95) I stood up and asked whether the system would contain any useful _metadata_.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.The Registry Editor on Windows on these systems also supports exporting .^ The registry is a heart and soul of any Windows system.
  • Windows Nt Registry Software Free Download 18 January 2010 4:17 UTC top.softlandmark.com [Source type: General]
  • Windows Me Registry Software Free Download 18 January 2010 4:17 UTC top.softlandmark.com [Source type: General]

^ Windows Registry Editor Version 5.00 .
  • Ways to Crack and Disable WGA Validation Tool and WGA Notifications plus Download and Install Bypassing Genuine Windows Validate Requirement » My Digital Life 18 January 2010 4:17 UTC www.mydigitallife.info [Source type: General]

^ The Registry is a heart and soul of any Windows system.
  • Free Windows Registry Tools 18 January 2010 4:17 UTC www.softpanorama.org [Source type: General]
  • Windows Me Registry - Registry Rinse, Registry File Repair, Free Window Registry Repair - and Others 18 January 2010 4:17 UTC shareme.com [Source type: General]

REG files in .Windows 9x/NT format.^ In Windows NT it is a bit trickier to locate the hives than it is in Windows 9x.
  • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

^ The registry is easier to locate in Windows 9x then it is in Windows NT. The registry is split between two different files, the User.dat and the System.dat .
  • Vernalex.com - Welcome 18 January 2010 4:17 UTC www.vernalex.com [Source type: FILTERED WITH BAYES]

^ Location: Windows NT4, 2000, XP In Windows NT it is a bit trickier to locate the hives than it is in Windows 9x.
  • The Windows Registry 18 January 2010 4:17 UTC www.go4expert.com [Source type: FILTERED WITH BAYES]

Data is stored in .REG files in the following syntax:[14]
[<Hive Name>\<Key Name>\<Subkey Name>]
"Value Name"=<Value type>:<Value data>
The Default Value of a key can be edited by using @ instead of "Value Name":
@=<Value type>:<Value data>
.String values do not require a <Value type> (see example).^ To access a particular folder a program opens it, specifying the path and the type of access required (for example read-only, or read/write), and receives a key.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ For this example I have decided to modify the value of the string WaitToKillAppTimeout.
  • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

^ Registry values (string-, DWORD- and binary value) Registry values can contain different types of data.
  • Optimizing the Windows Registry, the Registry Editor, registry tweaks and tracking changes to the registry. 18 January 2010 4:17 UTC www.optimizingpc.com [Source type: FILTERED WITH BAYES]

For example, to add the values "Value A", "Value B", "Value C", "Value D", and "Value E" to the HKLM\SOFTWARE\Microsoft key,
 
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft]
"Value A"="<String value data>"
"Value B"=hex:<Binary data>
"Value C"=dword:<DWORD value integer>
"Value D"=hex(7):<Multi-string value data>
"Value E"=hex(2):<Expandable string value data>
Data from .REG files can be added/merged with the registry by double-clicking these files or using the /s switch in the command line. .REG files can also be used to remove registry data.
.To remove a key (and all subkeys, values and data), the key name must be preceded by a minus sign ("-").^ Removes all long file names.
  • Serenity Windows 98 Program's Command Line Parameters and Registry Settings 18 January 2010 4:17 UTC www.mvps.org [Source type: FILTERED WITH BAYES]

^ Values - Values contain the actual data stored in a Key or Subkey.

^ The unset action removes a value from a key.

[14]
For example, to remove the <Key Name> key (and all subkeys, values and data),
[-HKEY_LOCAL_MACHINE\SOFTWARE\<Key Name>]
.To remove a value (and its data), the values to be removed must have a minus sign ("-") after the equal sign ("=").^ However, instead of a minus sign in front of the Key, the minus has to be placed after the equal sign of the Value.

^ For example to delete the [HKEY_LOCAL_MACHINE\SYSTEM\Setup] key the reg file would look like this: Code: REGEDIT4 [-HKEY_LOCAL_MACHINE\SYSTEM\Setup] The format used to delete individual values is similar, but instead of a minus sign in front of the whole key, place it after the equal sign of the value.
  • The Windows Registry 18 January 2010 4:17 UTC www.go4expert.com [Source type: FILTERED WITH BAYES]

[14]
For example, to remove only the "Value A" and "Value B" values (and their data) from the <Key Name> key,
 
[HKEY_LOCAL_MACHINE\SOFTWARE\<Key Name>]
"Value A"=-
"Value B"=-
To remove only the (Default) value of the key <Key Name> (and its data),
 
[HKEY_LOCAL_MACHINE\SOFTWARE\<Key Name>]
@=-

Command line editing

.The registry can be manipulated in a number of ways from the command line.^ There are two ways to delete a key from the Registry from the Command line.

^ Regedit Command Line Options Regedit has a number of command line options to help automate it's use in either batch files or from the command prompt.
  • The Windows Registry 18 January 2010 4:17 UTC www.go4expert.com [Source type: FILTERED WITH BAYES]

^ Reg is a command-line tool called the Console Registry Tool for Windows.

.The reg.exe utility tool is included in Windows XP and later versions of Windows.^ PremiumBooster works perfectly wit all versions of Windows up to and including Windows 7.

^ Reg is a command-line tool called the Console Registry Tool for Windows.

^ Windows XP comes with Backup Utility accessible via [Start] [All Programs] [Accessories] [System Tools] [Backup].
  • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

.Alternative locations for legacy versions of Windows include the Resource Kit CDs or the original Installation CD of Windows.^ Microsoft Windows XP, Vista as well as the latest version, Windows 7 - currently under Beta - include a feature known as System Restore.

^ CD (Chdir) operates only in the system directories of the current Windows installation, removable media, the root directory of any hard disk partition, or the local installation sources.
  • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

^ Notice, however, that no descriptions of individual Registry entries are provided, because such details are beyond the scope of the Windows 95 Resource Kit.

Also, a .REG file can be imported from the command line with the following command:
regedit.exe /s file
.The /s means the file will be silent merged to the Registry.^ The contents of the .reg file will be merged into the current registry followed by a confirmation dialog stating the information in the file has been successfully entered into the registry.
  • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

^ Once the changes have been made and saved, right clicking the file and using the [Merge] command adds the changed file back into the registry.
  • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

^ If you want to edit outside the confines of regedit, or if you are sure you want your additions to the registry to remain even if you have to merge, use Registration Files for your backup.
  • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

If the /s parameter is omitted the user will be asked to confirm the operation. .In Windows 98, Windows 95 and at least some configurations of Windows XP the /s switch also causes regedit.exe to ignore the setting in the registry that allows administrators to disable it.^ The registry should have died with Windows 95.
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

^ Windows 2k/XP Registry Tweaks .
  • SpeedGuide.net :: Windows 2k/XP Registry Tweaks 18 January 2010 4:17 UTC www.speedguide.net [Source type: FILTERED WITH BAYES]

^ Windows 2K/XP Registry Recovery .
  • Registry Recovery in Windows XP - PC Perspective Forums 18 January 2010 4:17 UTC forums.pcper.com [Source type: General]

.When using the /s switch Regedit does not return an appropriate return code if the operation fails, unlike reg.exe which does.^ If you give -q , it doesn't print the message but does return the non-zero exit code.

^ RegEdit /l location of System.dat /R location of User.dat /D Registry key to delete You cannot be in Windows at the time you use this switch.

^ Caution : Use the regedit /c option with extreme care, and only when you are sure that the specified .REG file contains a complete image of the Registry.

.The default association for .REG files in many versions of Microsoft Windows, starting with Windows 98, does require the user to confirm the merging to avoid a user mistake.^ Changes made to this data are written to a USER.DAT file stored in the user's subfolder of the Windows Profiles folder.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ I don't want to lose all of my files and settings (for 5 users) if it can be avoided.
  • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

^ User information is kept in files named NTUSER.DAT, which are stored in the Profiles subfolder of the main Windows folder.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

.Other command line options include a VBScript or JScript together with CScript, WMI or WMIC.exe and Windows PowerShell.^ Regedit Command Line Options Regedit has a number of command line options to help automate it's use in either batch files or from the command prompt.
  • The Windows Registry 18 January 2010 4:17 UTC www.go4expert.com [Source type: FILTERED WITH BAYES]

^ Double-click Userinit and set it’s value correctly such as C:\Windows\System32\Userinit.exe, Important Note: Make sure you include the comma at the end after Userinit.exe.
  • How To Edit Windows Registry Key Values without Booting in Windows » Raymond.CC Blog 18 January 2010 4:17 UTC www.raymond.cc [Source type: General]

^ Reg is a command-line tool called the Console Registry Tool for Windows.

.Registry permissions can be manipulated through the command line using the SubInACL.exe tool.^ Reg is a command-line tool called the Console Registry Tool for Windows.

^ The null problem wouldn't be a problem if we had a decent registry editor and useful command line utilities (possibly Powershell??
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ Regini.exe: Registry Change by Script Regview.exe (documented in Readme.htm) See Microsoft Registry Tools for more information.

For example, the permissions on the HKEY_LOCAL_MACHINE\SOFTWARE key can be displayed using:
subinacl /keyreg HKEY_LOCAL_MACHINE\SOFTWARE /display

Programs or scripts

.The registry can be edited through the APIs of the Advanced Windows 32 Base API Library (advapi32.dll).^ Editing the Windows 2000/XP Registry To edit the Registry, you need to use an editor, such as Regedit .
  • SpeedGuide.net :: Windows 2k/XP Registry Tweaks 18 January 2010 4:17 UTC www.speedguide.net [Source type: FILTERED WITH BAYES]

^ [Feb 24, 2007] How to back up, edit, and restore the registry in Windows XP and Windows Server 2003 .

^ Newer version is called Process Monitor: Process Monitor is an advanced monitoring tool for Windows that shows real-time file system, Registry and process/thread activity.

[15]
List of Registry API functions
RegCloseKey RegOpenKey RegConnectRegistry RegOpenKeyEx
RegCreateKey RegQueryInfoKey RegCreateKeyEx RegQueryMultipleValues
RegDeleteKey RegQueryValue RegDeleteValue RegQueryValueEx
RegEnumKey RegReplaceKey RegEnumKeyEx RegRestoreKey
RegEnumValue RegSaveKey RegFlushKey RegSetKeySecurity
RegGetKeySecurity RegSetValue RegLoadKey RegSetValueEx
RegNotifyChangeKeyValue RegUnLoadKey
.Many programming languages offer built-in runtime library functions or classes that enable programs to store settings in the registry (e.g.^ The Registry is a great thing for storing settings.
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

^ The Registry offers a number of benefits over other schemes for storing configuration data.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ And all applications should have a re-built registry entries function.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.Microsoft.Win32.Registry in VB.NET and C#, or TRegistry in Delphi).^ Chapter 6 is also available on the Net Microsoft Windows XP Registry Guide Chapter 6, Managing Registry-Based Policy .

.COM-enabled applications like Visual Basic 6 can use the WSH WScript.Shell object.^ I do not like XML - I'd prefer it if people used configuration files simplar to the format Apache httpd.conf file uses, or the config format that Visual Studio used to use to store it's project settings.
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

^ This program can be especially useful to those who build dlls in Visual Basic.

.Another way is to use the Windows Resource Kit Tool, Reg.exe by executing it from code,[16] although this is considered poor programming practice.^ Windows7 rtm 7600 build developers copy windows 7 CRASHING when useing programs Where's Guest Mode HELP!!!
  • Windows 7 Registry | Windows 7 News 18 January 2010 4:17 UTC windows7news.com [Source type: FILTERED WITH BAYES]

^ The Setup subkey under Hkey_Local_Machine \Software \Microsoft \Windows \CurrentVersion is used internally by Windows 95 for its Setup program.

^ Reg is a command-line tool called the Console Registry Tool for Windows.

.Similarly, scripting languages such as Perl (with Win32::TieRegistry), Windows Powershell and Windows Scripting Host also enable registry editing from scripts.^ Similarly, every time a new software is installed (or a software uninstalled), the changes are updated in the Windows Registry.

^ To answer this question, you must first look at several common reasons for editing the Windows registry.

^ How to back up, edit, and restore the registry in Windows XP and Windows Server 2003 322755 (http://support.microsoft.com/kb/322755/) How to back up, edit, and restore the registry in Windows 2000 .

Locations

.The Registry is stored in several files; depending upon the version of Windows, there will be different files and different locations for these files, but they are all on the local machine.^ For shared installations, these files are stored in the machine directory.

^ All versions of the Windows Operating System contain what is called the Windows Registry.

^ Deleted files, machine (windows) broke.
  • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

.The user-specific HKEY_CURRENT_USER user registry hive is stored in Ntuser.dat inside the user profile.^ User settings are stored in NTUSER.DAT and UsrClass.dat in your user profile.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ The HKEY_CURRENT_USER hive roams with the user's profile, making it portable.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ If user profiles have been enabled, there will also be a USER.DAT for each user, stored in the folder C:\Windows\Profiles\ .
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

.There is one of these per user; if a user has a roaming profile, then this file will be copied to and from a server at logout and login respectively.^ Copy copies one file to a target location.
  • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

^ YES indeed a simple config or INI file for each installed application in its own directory on a PER USER basis.
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

^ To include a help file (Tweak95.hlp and Tweak95.cnt from the downloads page) in the main Windows help contents copy both of these files into the c:\windows\help directory.
  • Serenity Windows 98 Program's Command Line Parameters and Registry Settings 18 January 2010 4:17 UTC www.mvps.org [Source type: FILTERED WITH BAYES]

Windows NT-based operating systems

.Windows NT-based systems store the registry in a binary hive format which is the same format that can be exported, loaded and unloaded by the Registry Editor in these operating systems.^ All versions of the Windows Operating System contain what is called the Windows Registry.

^ The Registry is a data base of essential information for applications and the Operating System.

^ Binary formats need special editors.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

The following Registry files are stored in %SystemRoot%\System32\Config\:
.
  • Sam – HKEY_LOCAL_MACHINE\SAM
  • Security – HKEY_LOCAL_MACHINE\SECURITY
  • Software – HKEY_LOCAL_MACHINE\SOFTWARE
  • System – HKEY_LOCAL_MACHINE\SYSTEM
  • Default – HKEY_USERS\.DEFAULT
  • Userdiff – Not associated with a hive.^ Once youve logged in as per STEP 3a , you need to move to the containing folder by typing: cd %windir%\system32\config Now you need to delete the currently used registry hive files by typing these lines one by one: del system del software del sam del security del default Now you need to copy the Restore Point files so that Windows can load from them.
    • Registry Recovery in Windows XP - PC Perspective Forums 18 January 2010 4:17 UTC forums.pcper.com [Source type: General]

    ^ System-wide Windows settings are stored under HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion.
    • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

    ^ Rename ' _REGISTRY_MACHINE_SAM ' to SAM Rename ' _REGISTRY_MACHINE_SECURITY ' to SECURITY Rename ' _REGISTRY_MACHINE_SOFTWARE ' to SOFTWARE Rename ' _REGISTRY_MACHINE_SYSTEM ' to SYSTEM Rename ' _REGISTRY_MACHINE_.DEFAULT ' to DEFAULT ( no dot!
    • Registry Recovery in Windows XP - PC Perspective Forums 18 January 2010 4:17 UTC forums.pcper.com [Source type: General]

    .Used only when upgrading operating systems.^ By using Registry Fix 3.0 regularly and fixing your Registry , your system will not only be more stable but will also help Windows and your software run faster.
    • Windows Me Registry - Registry Rinse, Registry File Repair, Free Window Registry Repair - and Others 18 January 2010 4:17 UTC shareme.com [Source type: General]

    ^ A Windows 98 computer may only have one user, but Windows NT/2000 supports multiple users and insists that you log on to the system to use it.
    • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

    ^ CD (Chdir) operates only in the system directories of the current Windows installation, removable media, the root directory of any hard disk partition, or the local installation sources.
    • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

    [17]
The following file is stored in each user's profile folder:
  • %UserProfile%\Ntuser.dat – HKEY_USERS\<User SID> (linked to by HKEY_CURRENT_USER)
For NT and XP, you also have the file
  • %UserProfile%\Local Settings\Application Data\Microsoft\Windows\Usrclass.dat (path is localized) – HKEY_USERS\<User SID>_Classes (HKEY_CURRENT_USER\Software\Classes)
For Vista you have the file
  • %UserProfile%\AppData\Local\Microsoft\Windows\Usrclass.dat (path is localized) – HKEY_USERS\<User SID>_Classes (HKEY_CURRENT_USER\Software\Classes)
.Windows 2000 keeps an alternate copy of the registry hives (.ALT) and attempts to switch to it when corruption is detected.^ Now you want to copy the registry files from there to your C:\Windows\bak : In the ' RP ' folder, you should see a sub-folder called ' snapshot '.
  • Registry Recovery in Windows XP - PC Perspective Forums 18 January 2010 4:17 UTC forums.pcper.com [Source type: General]

^ The process involves the replacing current registry hive files with backups of registry files that System Restore has saved at some point or from a very bare windows repair hive file.
  • Registry Recovery in Windows XP - PC Perspective Forums 18 January 2010 4:17 UTC forums.pcper.com [Source type: General]

^ To Backup/Restore the Windows Registry: Windows 9x For XP 2000 click here .

[18] .Windows XP and Windows Server 2003 do not maintain a System.alt hive because NTLDR on those versions of Windows can process the System.log file to bring up to date a System hive that has become inconsistent during a shutdown or crash.^ Registry Recovery in Windows 2K/XP INTRODUCTION If you’re reading this, you’ve probably just encountered one of the following errors: Windows could not start because the following file is missing or corrupt: \WINDOWS\SYSTEM32\CONFIG\SYSTEM Windows could not start because the following file is missing or corrupt: \WINDOWS\SYSTEM32\CONFIG\SYSTEMced Windows could not start because the following file is missing or corrupt: \WINDOWS\SYSTEM32\CONFIG\SOFTWARE Stop: c0000218 {Registry File Failure} The registry cannot load the hive (file): \SystemRoot\System32\Config\SOFTWARE or its log or alternate These errors occur as a result of files in the Registry Hive being corrupted or are missing.
  • Registry Recovery in Windows XP - PC Perspective Forums 18 January 2010 4:17 UTC forums.pcper.com [Source type: General]

^ If you install Windows 95 as an upgrade over Windows 3.1, some INI file settings are copied into the Registry, including settings from CONTROL.INI, PROGMAN.INI, SYSTEM.INI, and WIN.INI. .

^ The Services subkey in CurrentControlSet lists the Kernel device drivers, file system drivers, and Windows 95 service drivers that can be loaded at startup.

.In addition, the %Windir%\Repair folder contains a copy of the system's registry hives that were created after installation and the first successful startup of Windows.^ The Windows Registry offered a centralized database-like location to store application and system settings.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ Registry Junk: A Windows Fact of Life "the anal retentive systems administrator" Isn't the correct term "anally retentive"?
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

^ If I was limited to only one choice of backup before editing the registry I'd probably choose the Hive File method, but System Restore would also be a contender.
  • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

Windows 95, 98, and Me

.The registry files are named USER.DAT and SYSTEM.DAT are stored in the %WINDIR% directory.^ User information is kept in the file USER.DAT .
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ The contents of this branch are stored in the file SYSTEM.DAT in the Windows 9x Registry.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ It holds user preferences such as the display settings, the desktop appearance, system sounds, lists of recently opened files and so on.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

.In Windows Me, Classes.dat was added.^ UsrClass.dat have been added with Windows 2000 the rest is unchanged since at least Windows NT 4.0 .
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.Also, each user profile (if profiles are enabled) has its own USER.DAT in profile's directory.^ If user profiles have been enabled, there will also be a USER.DAT for each user, stored in the folder C:\Windows\Profiles\ .
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ Changes made to this data are written to a USER.DAT file stored in the user's subfolder of the Windows Profiles folder.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ User information is kept in files named NTUSER.DAT, which are stored in the Profiles subfolder of the main Windows folder.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

Windows 3.11

.The registry file is Reg.dat, system.dat and is stored in the C:\WINDOWS directory.^ The Windows 9x registry comprises two files: system.dat and user.dat.

^ Under Windows 9x/Me, system information is kept in the file SYSTEM.DAT .
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ The contents of this branch are stored in the file SYSTEM.DAT in the Windows 9x Registry.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

.These files also contain system registry info: user.dat and is stored in the C:\windows\profiles\<username>\user.dat directory.^ For shared installations, these files are stored in the machine directory.

^ Changes made to this data are written to a USER.DAT file stored in the user's subfolder of the Windows Profiles folder.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ Under Windows 9x/Me, system information is kept in the file SYSTEM.DAT .
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

Backups and recovery

Windows supports several methods to back up and restore the registry:
.
  • System Restore can back up the registry and restore it as long as Windows is bootable, or from the Windows Recovery Environment starting with Windows Vista.
  • NTBackup can back up the registry as part of the System State and restore it.
  • On Windows NT-based systems, the Last Known Good Configuration option in startup menu relinks the HKLM\SYSTEM\CurrentControlSet key, which stores hardware and device driver information.
  • Windows 98 and Windows Me include command line (Scanreg.exe) and GUI (Scanregw.exe) registry checker tools to check and fix the integrity of the registry, create up to five automatic regular backups by default and restore them manually or whenever corruption is detected.^ How to backup your windows registry .

    ^ Reg is a command-line tool called the Console Registry Tool for Windows.

    ^ A program called the Windows Registry Checker ( SCANREGW.EXE ) runs every time at start-up.
    • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

    .The registry checker tool backs up the registry, by default, to %Windir%\Sysbckup Scanreg.exe can also run from MS-DOS.
  • The Windows 95 CD-ROM included an Emergency Recovery Utility (ERU.exe) and a Configuration Backup Tool (Cfgback.exe) to back up and restore the registry.^ A program called the Windows Registry Checker ( SCANREGW.EXE ) runs every time at start-up.
    • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

    ^ The registry should have died with Windows 95.
    • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

    ^ Backing up and Restoring .
    • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

    Additionally Windows 95 backs up the registry to the files system.da0 and user.da0 on every successful boot.

Policy

Group policy

.Windows 2000 and later versions of Windows use Group Policy to enforce Registry settings.^ Using Group Policy settings, and deploying User Profiles.

^ System settings are what the registry should be used for.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ If you install Windows 95 as an upgrade over Windows 3.1, some INI file settings are copied into the Registry, including settings from CONTROL.INI, PROGMAN.INI, SYSTEM.INI, and WIN.INI. .

.Policy may be applied locally to a single computer using GPEdit.msc, or to multiple computers in a domain using gpmc.msc.^ A Windows 98 computer may only have one user, but Windows NT/2000 supports multiple users and insists that you log on to the system to use it.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ And even if permissions weren’t an issue domain users with roaming profiles carry application settings with them to other computers, so profiles that need to be updated might not even be locally accessible.
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

^ To make Windows use multiple Start Menu Columns instead of a single scrolling column, like Windows 9x had, Also if you are using Classic Mode in XP .

Legacy systems

.With Windows 95, Windows 98, Windows Me and Windows NT, administrators can use a special file to be merged into the registry, called a policy file (POLICY.POL).^ The registry should have died with Windows 95.
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

^ Only Windows 95 and Windows 98.

^ Registry software for Windows 95,98,ME,NT,2000 and XP .

.The policy file allows administrators to prevent non-administrator users from changing registry settings like, for instance, the security level of Internet Explorer and the desktop background wallpaper.^ When you make changes to the desktop configuration, the settings are added to the Registry.

^ In the example above, the Windows Registry would store the User Account settings of the account used by you and the spouse, as well as the account used by Junior Any change made by any user to his/ her Control Panel settings, File Associations or System Policies (even the Desktop Wallpaper!

^ It lets you choose which changes to accept and to ignore, and creates an Undo file so that you can revert to the previous version of the Registry if problems occur.

.The policy file is primarily used in a business with a large number of computers where the business needs to be protected from rogue or careless users.^ Cleaning After a number of software installations and un-installations, the registry becomes full of dangling file reference pointing to where the files used to reside but no longer exist.

^ Using Group Policy settings, and deploying User Profiles.

^ JM's remark about each user getting their own file was a response to the claim that using INI files had locking issues, he wasn't talking about the registry in that case.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.The default extension for the policy file is .POL.^ HKCU\ControlPanel\Notifications\Default And change to the names of other wav files in your \Windows directory without the ` .wav ` extension.
  • Windows Mobile 5 Registry Tweaks - MoDaCo 18 January 2010 4:17 UTC wiki.modaco.com [Source type: FILTERED WITH BAYES]

.The policy file filters the settings it enforces by user and by group (a "group" is a defined set of users).^ Using Group Policy settings, and deploying User Profiles.

^ It holds user preferences such as the display settings, the desktop appearance, system sounds, lists of recently opened files and so on.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ I don't want to lose all of my files and settings (for 5 users) if it can be avoided.
  • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

.To do that the policy file merges into the registry, preventing users from circumventing it by simply changing back the settings.^ It cannot be merged back into the registry like a Registration File.
  • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

^ It lets you choose which changes to accept and to ignore, and creates an Undo file so that you can revert to the previous version of the Registry if problems occur.

^ Also, change the attribute for the Boot.ini file back to a read-only state after you finish this procedure.
  • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

.The policy file is usually distributed through a LAN, but can be placed on the local computer.^ System policies can override settings in these two .DAT files to enforce user-specific and computer-specific information, as described in Chapter 15, "User Profiles and System Policies."

^ {CLSID of special folder} Where the special folder is a sub folder of another special folder (usually, if not always My Computer) explorer /e,root,::{CLSID of parent}/::{CLSID of special folder} Where the special folder is part of the file system .
  • Serenity Windows 98 Program's Command Line Parameters and Registry Settings 18 January 2010 4:17 UTC www.mvps.org [Source type: FILTERED WITH BAYES]

.The policy file is created by a free tool by Microsoft that goes by the filename poledit.exe for Windows 95/Windows 98 and with a computer management module for NT-based systems.^ Only Windows 95 and Windows 98.

^ Registry software for Windows 95,98,ME,NT,2000 and XP .

^ Its filename is REGEDIT.EXE under Windows 9x and REGEDT32.EXE under Windows NT. .
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

.The editor requires administrative permissions to be run on systems that uses permissions.^ XP requires you to use the System State backup in this instance.
  • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

^ Runs in unattended mode using the System Agent-aware settings in the SETn registry key.
  • Serenity Windows 98 Program's Command Line Parameters and Registry Settings 18 January 2010 4:17 UTC www.mvps.org [Source type: FILTERED WITH BAYES]

^ I'm guessing you guys are the ones that write apps that need Administrator privileges to run because you think apps have write permissions to their install directory.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.The editor can also directly change the current registry settings of the local computer and if the remote registry service is installed and started on another computer it can also change the registry on that computer.^ Registry Editor can be used to view or modify a Registry on a local computer or on another computer over a network.

^ When you make changes to the desktop configuration, the settings are added to the Registry.

^ This is in part because I don't want to clutter my own (or other peoples) registry with application-specific "junk", but also because this way I can copy my application to another computer and still keep all my settings.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.The policy editor loads the settings it can change from .ADM files, of which one is included, that contains the settings the Windows shell provides.^ Changes made to this data are written to a USER.DAT file stored in the user's subfolder of the Windows Profiles folder.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ Do you perform frequent searches and wish that the native editor that ships with Windows included more advanced options?

^ Index Tweaking Windows 95=Tweak95.hlp If changes do not take effect delete the hidden file Windows.gid or type in the Start - Run dialog box .
  • Serenity Windows 98 Program's Command Line Parameters and Registry Settings 18 January 2010 4:17 UTC www.mvps.org [Source type: FILTERED WITH BAYES]

.The .ADM file is plain text and supports easy localisation by allowing all the strings to be stored in one place.^ What the registry should've been was a database tracking localized .ini files, which could be binary or plain-text files containing the same information.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ Either way, only power users are going to touch these things, and power users will be happier with easy to maniuplate and move around text files.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ You've got a system with all the advantages of a single settings DB with all the advantages of letting the user edit simple text files.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.INI file virtualization

.Windows NT kernels support redirection of INI file-related APIs into a virtual file in a Registry location such as HKEY_CURRENT_USER using a feature called "InifileMapping".[19] This functionality was introduced to allow legacy applications written for 16-bit versions of Windows to be able to run under Windows NT platforms on which the System folder is no longer considered an appropriate location for user-specific data or configuration.^ Most applications today use registry to store configuration and other important data.

^ Changes made to this data are written to a USER.DAT file stored in the user's subfolder of the Windows Profiles folder.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ Sort of like a Windows 3.1 INI file.
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

.Non-compliant 32-bit applications can also be redirected in this manner, even though the feature was originally intended for 16-bit applications.^ Although Microsoft discourages using INI files in favor of Registry entries, some applications (particularly 16-bit Windows-based applications) still use INI files.

^ Most 32-bit Windows applications store configuration settings in the Registry.
  • The Windows Registry 18 January 2010 4:17 UTC www.tech-pro.net [Source type: Reference]

^ It could watch the original INI file even when the application isn't running and then suck any changes into that internal DB. Viola!
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

Registry virtualization

.Windows Vista has introduced limited Registry virtualization, whereby poorly written applications that write user data to a read-only system location (such as the HKEY_LOCAL_MACHINE hive) can be redirected to a more appropriate location, without changing the application itself.^ It is possible to write Windows applications that don't use the registry in any way.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ Actually there is nothing else you can do with Windows Registry besides reading its data and write data to it ;).
  • Working with Windows Registry 18 January 2010 4:17 UTC www.c-sharpcorner.com [Source type: FILTERED WITH BAYES]

^ A user also can make changes to the registry indirectly via software applications.

.The operation is transparent to the application, as it does not know that its Registry operations have been directed elsewhere.^ The Registry is a data base of essential information for applications and the Operating System.

.Similarly, application virtualization redirects all of an application's Registry operations to a non-Registry backed location, such as a file.^ In fact, all applications I write use INI-files and not the registry.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ The Vista registry/filesystem extension is nice BUT, implementing this in an application would involve having two code paths: one for vista, and one for all other Windows OSs.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ And all applications should have a re-built registry entries function.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.Used together with file virtualization, this approach allows applications to run without being installed on the location machine.^ NewKey (use an "&" without the quotes, in front of any character and it will allow you to use the keyboard) 5.

^ Jacob on August 29, 2007 5:51 AM Using the registry means that you're updating global machine state to install your application.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ If you're working with an application that runs on a network - an INI file on a network share makes a ton more sense than using registry entries.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

.Lastly, the Application Compatibility Toolkit[20] provides shims that can transparently redirect HKEY_LOCAL_MACHINE or HKEY_CLASSES_ROOT Registry operations to HKEY_CURRENT_USER to address "LUA" bugs that cause applications not to work for limited users.^ That’s because uninstallers typically delete their application’s system-wide settings from the HKEY_LOCAL_MACHINE part of the Registry and any per-user settings of the user running the uninstaller from HKEY_CURRENT_USER. But what happens to the per-user settings of the other users that used the application?
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

^ If you're working with an application that runs on a network - an INI file on a network share makes a ton more sense than using registry entries.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ Plus, most users are dumb enough to delete files as they are easily found, but know the Registry is off limits to newbies, so more secure.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

Windows 9x operating systems

.On Windows 9x computers, an older installation can have a very large registry that slows down the computer's startup and can make the computer unstable.^ Slowing down the computer at an alarming rate.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ File/Folder/MFT/Registry Fragmentation, open files, amount of temporary files, amount of cache files are but some of the things that cause slow down over time.
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

^ The various Hkey_Local_Machine \Software Description subkeys contain the names and version numbers of the software installed on the local computer (if that software writes information to the Registry as part of its installation process).

This has led to frequent criticisms that the registry leads to instability. .However, as the on-disc structure of the registry is entirely different on the NT line of Operating Systems (including Windows XP and Vista) than Windows 9x series OS,[1] slowdown due to registry bloat now occurs much less frequently.^ Of course, this matters much less now than it did in 1995.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ Registry software for Windows 95,98,ME,NT,2000 and XP .

^ Windows 2K/XP Registry Recovery .
  • Registry Recovery in Windows XP - PC Perspective Forums 18 January 2010 4:17 UTC forums.pcper.com [Source type: General]

[citation needed]

Equivalents in other operating systems

.In contrast to the Windows registry's binary-based database model, some other operating systems use separate plain-text files for daemon and application configuration, but group these configurations together for ease of management.^ Most applications today use registry to store configuration and other important data.

^ It is possible to write Windows applications that don't use the registry in any way.
  • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

^ Please, stop using the registry and start using standalone text files!
  • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

.
  • Under Unix-like operating systems e.g.^ It just irks me how well other operating systems can handle simple things like this, when windows can't.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    .Linux that follow the Filesystem Hierarchy Standard, system-wide configuration files (information similar to what would appear in HKEY_LOCAL_MACHINE on Windows) are traditionally stored in files in /etc/ and its subdirectories, or sometimes in /usr/local/etc.^ LocalMachine - Stores configuration information for the local machine.
    • Working with Windows Registry 18 January 2010 4:17 UTC www.c-sharpcorner.com [Source type: FILTERED WITH BAYES]

    ^ The filename of the dropped file is as follows: scvhost.exe This EXE file is dropped into and executed from the "%SYSTEMROOT%\SYSTEM32 " folder, where it drops a DLL file: scvhost.asf and, sometimes, a .DAT file: 00540.DAT Although the name of this .DAT file appears to be random.
    • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

    ^ Subkeys describing the current user's software settings, using the same structure as Hkey_Local_Machine \Software and containing application-specific information stored in WIN.INI or private initialization files under Windows 3.x .

    .Per-user information (information that would be roughly equivalent to that in HKEY_CURRENT_USER) is stored in hidden directories and files (that start with a period/full stop) within the user's home directory.^ For shared installations, these files are stored in the machine directory.

    ^ XML files in the same directory as the EXE file - real smart when c:\program files is READ ONLY to the average user.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ Windows 95 In the Windows directory there are several hidden files, four of these will be SYSTEM.DAT & USER.DAT, your current registry, and SYSTEM.DA0 & USER.DA0, a backup of your registry.
    • The Windows Registry 18 January 2010 4:17 UTC www.go4expert.com [Source type: FILTERED WITH BAYES]

    However XDG-compliant applications should refer to the environment variables defined in the Base Directory specification[21].
  • Applications running on Apple Inc.'s Mac OS X operating system typically store settings in property list files which are usually stored in each user's Library folder.
  • RISC OS also allows applications to be copied into directories easily, as opposed to the separate installation program that typifies Windows applications. .If one wishes to remove the application, it is possible to simply delete the folder belonging to the application.^ Then to copy programs you would only need one (or two) folders, and applications could automatically generate new ones if you forgot one.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ It's possible to stop an application from working by editing or removing configuration values.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ I downloaded it, decompressed the folder and BAM, there were instructions simply telling me to copy the IE folder into the applications folder and it would be ready to run.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    [22] .This will often not remove configuration settings which are stored independently from the application, usually within the computer's !Boot structure, in !Boot.Choices, but potentially anywhere on a network fileserver.
  • IBM AIX (a Unix variant) uses a registry component called Object Data Manager (ODM).^ Most applications today use registry to store configuration and other important data.

    ^ The Registry is a great thing for storing settings.
    • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

    ^ A set of network-independent functions can be used to set and query configuration information, allowing system administrators to examine configuration data on remote networked computers.

    .The ODM is used to store information about system and device configuration.^ Information about hardware devices on the system .

    ^ Users - Stores information about the default user configuration.
    • Working with Windows Registry 18 January 2010 4:17 UTC www.c-sharpcorner.com [Source type: FILTERED WITH BAYES]

    ^ Most applications today use registry to store configuration and other important data.

    .An extensive set of tools and utilities provides users with means of extending, checking, correcting the ODM database.^ That means that you should have a set of registry tools.

    ^ Shouldn't any sane application provide each user with their own settings file in the their own home directory?"
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ The network administrator can restrict users from being able to use Registry Editor to modify the Registry by setting a system policy named Disable Registry Editing Tools.

    .The ODM stores its information in several files, default location is /etc/objrepos.
  • The GNOME desktop environment uses a registry-like interface called GConf for storing configuration settings for the desktop and applications.^ Most applications today use registry to store configuration and other important data.

    ^ The Windows Registry offered a centralized database-like location to store application and system settings.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ When you make changes to the desktop configuration, the settings are added to the Registry.

    .However, in GConf, all application settings are stored in separate files, thereby eliminating a single point of failure.^ Isn't that a single point of failure?
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ I like to store all my application configuration in a xml file.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ As for storing separate settings files...
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    .Conversely, this also creates multiple points of failure, and the likelyhood of one or more files being destroyed is increased.
  • The Elektra Initiative provides an alternative back-end for text configuration files for the Linux operating system, similar to the registry.
  • While not an operating system, the Wine compatibility layer, which allows Windows software to run on a Unix-like system, also employs a Windows-like registry as text files in the WINEPREFIX folder: system.reg (HKEY_LOCAL_MACHINE), user.reg (HKEY_CURRENT_USER) and userdef.reg.^ Sort of like a Windows 3.1 INI file.
    • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

    ^ It cannot be merged back into the registry like a Registration File.
    • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

    ^ One of them is labeled Operating System.
    • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

    [23]

Advantages and disadvantages

The Windows centralized Registry has a number of advantages over legacy INI files:[24]
.
  • Strongly-typed data can be stored in the Registry, as opposed to only textual information in INI files.
  • Separation of machine configuration from user configuration.^ Users - Stores information about the default user configuration.
    • Working with Windows Registry 18 January 2010 4:17 UTC www.c-sharpcorner.com [Source type: FILTERED WITH BAYES]

    ^ The choices were not limited to ini files or Registry.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ If applications need per-user configuration but can't store it in the Registry, where can they store it?
    • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

    .When a user logs into a Windows NT computer, the user-based registry settings are loaded from a user-specific path rather than from a read-only system location.^ Windows filesystem convention for system level, non-user-specific settings” .
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ The standard for Windows programs are Registry, HKCU for users-based settings, HKLM for computer-based configuration.
    • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

    ^ Can only be set in registry .
    • Serenity Windows 98 Program's Command Line Parameters and Registry Settings 18 January 2010 4:17 UTC www.mvps.org [Source type: FILTERED WITH BAYES]

    .This allows multiple users to share the same machine, and also allows programs to work for a least-privilege user.
  • Standardization of the method of storing configuration data across diverse applications.
  • The registry can be accessed over a network connection for remote management/support, including from scripts, using the standard set of APIs, as long as the Remote Registry service is running and firewall rules permit this.
  • The entire registry can be backed up more easily as it is just a small number of files in specific locations.
  • Since accessing the registry does not require parsing, it may be read from or written to more quickly than an ini file.^ Most applications today use registry to store configuration and other important data.

    ^ For shared installations, these files are stored in the machine directory.

    ^ If I recall, .ini files were the same way.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    .However, the centralized nature of the registry requires that the entire file be processed once per boot.
  • Portions of settings like any subset of an application configuration can be saved in a text-based .^ Windows Registry is a central database for application configuration settings and other information required by the applications.
    • Working with Windows Registry 18 January 2010 4:17 UTC www.c-sharpcorner.com [Source type: FILTERED WITH BAYES]

    ^ If applications need per-user configuration but can't store it in the Registry, where can they store it?
    • Mark's Blog : Registry Junk: A Windows Fact of Life 18 January 2010 4:17 UTC blogs.technet.com [Source type: FILTERED WITH BAYES]

    ^ I like to store all my application configuration in a xml file.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    REG file, which can be edited with any text editor later. .REG files can easily be merged back into the registry both by unattended batch file or by the user just double-clicking on the file without harming any setting that is not explicitly stated in the .REG file. .This is very useful for administrators and support personnel who want to pre-set or pre-configure only a few options like approving the EULA of a certain application.
  • The registry is constructed as a database, and offers database-like features, such as atomic updates.^ Windows Registry is a central database for application configuration settings and other information required by the applications.
    • Working with Windows Registry 18 January 2010 4:17 UTC www.c-sharpcorner.com [Source type: FILTERED WITH BAYES]

    ^ The Windows Registry offered a centralized database-like location to store application and system settings.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ Can only be set in registry .
    • Serenity Windows 98 Program's Command Line Parameters and Registry Settings 18 January 2010 4:17 UTC www.mvps.org [Source type: FILTERED WITH BAYES]

    .If two processes attempt to update the same registry value at the same time, one process's change will precede the other's, and the overall consistency of the data is maintained.^ Most applications today use registry to store configuration and other important data.

    ^ In fact, the registry will accumulate, over time, numerous errors that lead to the need to reformat windows every other year or so (or just resign yourself to the errors).
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ Simply put, installing RegHance along with these tools makes it easy to observe and investigate registry changes that spyware can attempt to make or succeed in making.

    .With changes in a file system, such race conditions can result in inconsistent data which doesn't match either attempted update.^ Changes the File System to normal Dos.
    • Serenity Windows 98 Program's Command Line Parameters and Registry Settings 18 January 2010 4:17 UTC www.mvps.org [Source type: FILTERED WITH BAYES]

    ^ Do not, however, indiscriminately zero out EditFlag; if you do so in a system ProgID such as Drive or AudioCD, it completely disappears from the File Types list.

    ^ If the data was stored outside of the registry, it would still require some kind of configuration file change.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    .Windows Vista provides transactional updates to the registry, extending the atomicity guarantees across multiple key and/or value changes, with traditional commit-abort semantics.^ The Vista registry/filesystem extension is nice BUT, implementing this in an application would involve having two code paths: one for vista, and one for all other Windows OSs.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ Understanding Registry Editor is much easier if you think of the left pane as the Keys Pane and the right side as the Values Pane.
    • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

    ^ [If] a value exists in the .reg file and also exists in the modified registry [Then] the value will be changed in the registry.
    • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

    .(Note that NTFS provides such support for the file system as well, so the same guarantees could be obtained with traditional configuration files.^ Do not, however, indiscriminately zero out EditFlag; if you do so in a system ProgID such as Drive or AudioCD, it completely disappears from the File Types list.

    ^ The Services key contains information to control the loading and configuration of drivers, file systems, and so on.

    ^ What the registry should've been was a database tracking localized .ini files, which could be binary or plain-text files containing the same information.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    )
However, the centralized Registry introduces some problems:
.
  • The registry duplicates much of the functionality of the file system.
  • Centralizing configurations makes it difficult to back up and recover individual applications.
  • Because the Registry structure is contained in binary files, damage to the registry itself is difficult or impossible to repair.^ Make sure to back up the registry before you modify it.

    ^ Do not repair sectors in hidden and system files .
    • Serenity Windows 98 Program's Command Line Parameters and Registry Settings 18 January 2010 4:17 UTC www.mvps.org [Source type: FILTERED WITH BAYES]

    ^ This is equivalent to backing up the entire registry.
    • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

    .Because information required for loading device drivers is stored in the registry[25], a damaged registry may prevent a Windows system from booting successfully.^ Disable disables a Windows system service or driver.
    • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

    ^ Information about hardware devices on the system .

    ^ Enable enables a Windows system service or driver.
    • windows registry problem? 18 January 2010 4:17 UTC www.windowsbbs.com [Source type: FILTERED WITH BAYES]

    .While damaged configuration files can have the same result to other operating systems, the damage can be more easily repaired by booting to another operating system, and using a text editor.
  • Installers and uninstallers become complex, much more than just copying files into a folder.
  • Applications that make use of the registry to store and retrieve their settings are unsuitable for use on portable devices used to carry applications from one system to another.
  • Since an application's configuration is centralized away from the application itself, it is often not possible to copy installed applications that use the Registry to another computer.^ Most applications today use registry to store configuration and other important data.

    ^ The Windows Registry offered a centralized database-like location to store application and system settings.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ I am no more certain that I will capture all settings using the configuration file method than I was certain I would find all the settings using the registry.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    .This means that software usually has to be reinstalled from original media on a computer upgrade or rebuild, rather than just copying the user and software folder to the new computer.
  • The Windows Registry is said to be a single point of failure.^ Isn't that a single point of failure?
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ Let me count the ways : The registry is a single point of failure .
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    ^ Just copy over the whole folder.
    • Coding Horror: Was The Windows Registry a Good Idea? 18 January 2010 4:17 UTC www.codinghorror.com [Source type: General]

    [26][27]

See also

Notes

  1. ^ When applications fail to execute because they request more privileges than they require (and are denied those privileges), this is known as a limited user application (LUA) bug.

Footnotes

  1. ^ a b "Windows 2000 Registry: Latest Features and APIs Provide the Power to Customize and Extend Your Apps". http://msdn.microsoft.com/msdnmag/issues/1100/Registry/. Retrieved 2007-07-19. 
  2. ^ Raymond Chen, "Why do registry keys have a default value?"
  3. ^ "Registry hives". http://msdn2.microsoft.com/en-us/library/ms724877.aspx. Retrieved 2007-07-19. 
  4. ^ Why is a registry file called a "hive"?
  5. ^ "Designed for Windows XP Application Specification". Microsoft. 2002-08-20. http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=209e3d65-f0be-4eef-8602-73bb9bc29d54. Retrieved 2009-04-08. 
  6. ^ "Description of the Microsoft Windows registry". http://support.microsoft.com/kb/256986. Retrieved 2008-09-25. 
  7. ^ "HKEY_CURRENT_USER". Microsoft. 2009. http://technet.microsoft.com/en-us/library/cc976337.aspx. Retrieved 2009-04-08. 
  8. ^ "HKEY_LOCAL_MACHINE". Microsoft. 2009. http://technet.microsoft.com/en-us/library/cc959046.aspx. Retrieved 2009-04-08. 
  9. ^ Description of the HKEY_DYN_DATA Registry Key in Windows 95, Windows 98, and Windows 98 SE
  10. ^ A Closer Look at HKEY_DYN_DATA
  11. ^ Using Registry Editor in Real Mode
  12. ^ Microsoft's Windows 2000 Security Hardening Guide version 1.3, published May 15, 2003
  13. ^ Offline Registry Editor user manual/doc
  14. ^ a b c d How to add, modify, or delete registry subkeys and values by using a registration entries (.reg) file
  15. ^ "Reading and Writing Registry Values with Visual Basic". http://www.windowsdevcenter.com/lpt/a/5016. Retrieved 2007-07-19. 
  16. ^ "REG command in Windows XP". http://www.petri.co.il/reg_command_in_windows_xp.htm. Retrieved 2007-07-19. 
  17. ^ Microsoft Corporation
  18. ^ "Inside the Registry". http://www.microsoft.com/technet/archive/winntas/tips/winntmag/inreg.mspx?mfr=true. Retrieved 2007-12-28. 
  19. ^ "Chapter 26 - Initialization Files and the Registry". Microsoft. http://www.microsoft.com/technet/archive/ntwrkstn/reskit/26_ini.mspx?mfr=true. Retrieved 2008-03-03. 
  20. ^ "Microsoft Application Compatibility Toolkit 5.0". Microsoft. http://technet.microsoft.com/en-us/appcompat/aa905102.aspx. Retrieved 2008-07-26. 
  21. ^ "XDG Base Directory Specification". http://standards.freedesktop.org/basedir-spec/latest/index.html. 
  22. ^ "RISC OS tour". http://www.riscos.org/tour/index.html. Retrieved 2007-07-19. 
  23. ^ 3.2. Using the Registry and Regedit (Wine User Guide)
  24. ^ "Windows 95 Architecture Components". Microsoft. http://www.microsoft.com/technet/archive/win95/rk31_arc.mspx?mfr=true. Retrieved 2008-04-29. 
  25. ^ http://technet.microsoft.com/en-us/library/cc959506.aspx
  26. ^ http://www.ibm.com/developerworks/web/library/wa-cranky66a.html
  27. ^ http://it.toolbox.com/blogs/minimalit/windows-registry-design-17993

References

  • Russinovich, Mark E.; Solomon, David A. (2005). .Microsoft Windows Internals (Fourth Edition ed.^ The Setup subkey under Hkey_Local_Machine \Software \Microsoft \Windows \CurrentVersion is used internally by Windows 95 for its Setup program.

    ^ Windows XP Professional Windows XP Home Edition Windows XP Update Windows XP Expert Zone Microsoft Security Desktop Deployment Res.
    • Backing Up and Restoring the Windows XP Registry 18 January 2010 4:17 UTC www.theeldergeek.com [Source type: FILTERED WITH BAYES]

    ). Microsoft Press. pp. 183–236. ISBN 978-0-7356-1917-3.
     

External links


Citable sentences

Up to date as of December 29, 2010

Here are sentences from other pages on Windows Registry, which are similar to those in the above article.








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