Understanding the purpose of each subtree can help you locate specific keys and values
in the Registry. The following five subtrees or subtree keys are displayed in the Registry Editor.
HKEY_CLASSES_ROOT Contains software configuration data: object linking and embedding (OLE) and file-class association data. This subtree points to the Classes subkey under HKEY_LOCAL_MACHINE\SOFTWARE.
HKEY_CURRENT_USER Contains data about the current user. Retrieves a copy of each user account used to log on to the computer from the NTUSER.DAT file and stores it in the %systemroot%\Profiles\username key. This subkey points to the same data contained in HKEY_USERS\SID_currently_logged_on_user. This subtree
takes precedence over HKEY_LOCAL_MACHINE for duplicated values.
HKEY_LOCAL_MACHINE Contains all configuration data for the local computer, including hardware and operating system data such as bus type, system memory, device drivers, and startup control data. Applications, device drivers, and the operating system use this data to set the computer configuration. The data in this subtree
remains constant regardless of the user.
HKEY_USERS Contains the .DEFAULT subkey, which holds the system default settings (system default profile) used to display the CTRL+ALT+DELETE logon screen, and the Security Identifier (SID) of the current user.
HKEY_CURRENT_CONFIG Contains data on the active hardware profile extracted from the SOFTWARE and SYSTEM hives. This information is used to configure settings such as the device drivers to load and the display resolution to use.
The HKEY_LOCAL_MACHINE Subtree
HKEY_LOCAL_MACHINE provides a good example of the subtrees in the Registry for two reasons:
■ The structure of all subtrees is similar.
■ HKEY_LOCAL_MACHINE contains information specific to the local computer and is always the same, regardless of the user who is logged on. The HKEY_LOCAL_MACHINE root key has five subkeys.
Showing posts with label Registry Editor. Show all posts
Showing posts with label Registry Editor. Show all posts
December 3, 2009
Subkeys of HKEY_LOCAL_MACHINE
Understanding the purpose of each subtree can help you locate specific keys and values
in the Registry. The following five subtrees or subtree keys are displayed in the Registry Editor.
HKEY_CLASSES_ROOT Contains software configuration data: object linking and embedding (OLE) and file-class association data. This subtree points to the Classes subkey under HKEY_LOCAL_MACHINE\SOFTWARE.
HKEY_CURRENT_USER Contains data about the current user. Retrieves a copy of each user account used to log on to the computer from the NTUSER.DAT file and stores it in the %systemroot%\Profiles\username key. This subkey points to the same data contained in HKEY_USERS\SID_currently_logged_on_user. This subtree
takes precedence over HKEY_LOCAL_MACHINE for duplicated values.
HKEY_LOCAL_MACHINE Contains all configuration data for the local computer, including hardware and operating system data such as bus type, system memory, device drivers, and startup control data. Applications, device drivers, and the operating system use this data to set the computer configuration. The data in this subtree
remains constant regardless of the user.
HKEY_USERS Contains the .DEFAULT subkey, which holds the system default settings (system default profile) used to display the CTRL+ALT+DELETE logon screen, and the Security Identifier (SID) of the current user.
HKEY_CURRENT_CONFIG Contains data on the active hardware profile extracted from the SOFTWARE and SYSTEM hives. This information is used to configure settings such as the device drivers to load and the display resolution to use.
The HKEY_LOCAL_MACHINE Subtree
HKEY_LOCAL_MACHINE provides a good example of the subtrees in the Registry for two reasons:
■ The structure of all subtrees is similar.
■ HKEY_LOCAL_MACHINE contains information specific to the local computer and is always the same, regardless of the user who is logged on. The HKEY_LOCAL_MACHINE root key has five subkeys.
in the Registry. The following five subtrees or subtree keys are displayed in the Registry Editor.
HKEY_CLASSES_ROOT Contains software configuration data: object linking and embedding (OLE) and file-class association data. This subtree points to the Classes subkey under HKEY_LOCAL_MACHINE\SOFTWARE.
HKEY_CURRENT_USER Contains data about the current user. Retrieves a copy of each user account used to log on to the computer from the NTUSER.DAT file and stores it in the %systemroot%\Profiles\username key. This subkey points to the same data contained in HKEY_USERS\SID_currently_logged_on_user. This subtree
takes precedence over HKEY_LOCAL_MACHINE for duplicated values.
HKEY_LOCAL_MACHINE Contains all configuration data for the local computer, including hardware and operating system data such as bus type, system memory, device drivers, and startup control data. Applications, device drivers, and the operating system use this data to set the computer configuration. The data in this subtree
remains constant regardless of the user.
HKEY_USERS Contains the .DEFAULT subkey, which holds the system default settings (system default profile) used to display the CTRL+ALT+DELETE logon screen, and the Security Identifier (SID) of the current user.
HKEY_CURRENT_CONFIG Contains data on the active hardware profile extracted from the SOFTWARE and SYSTEM hives. This information is used to configure settings such as the device drivers to load and the display resolution to use.
The HKEY_LOCAL_MACHINE Subtree
HKEY_LOCAL_MACHINE provides a good example of the subtrees in the Registry for two reasons:
■ The structure of all subtrees is similar.
■ HKEY_LOCAL_MACHINE contains information specific to the local computer and is always the same, regardless of the user who is logged on. The HKEY_LOCAL_MACHINE root key has five subkeys.
How to Edit the Registry Using the Registry Editor
Setup installs Registry Editor (REGEDIT.EXE) in the %systemroot%\System32 directory during installation. However, because most users do not need to use Registry Editor, it does not appear on the Start menu. To start Registry Editor, click Run on the Start menu, type Regedit, and then click OK. Although Registry Editor allows you to perform manual edits on the Registry, it is intended for troubleshooting and problem resolution. You should make most configuration changes through either Control Panel or Administrative Tools. However, some
configuration settings can be made only directly through the Registry.
Caution Using Registry Editor incorrectly can cause serious, system-wide problems that
could require reinstallation of Windows XP Professional. When using Registry Editor to view or
edit data, use a program such as Windows Backup to save a backup copy of the Registry file
before viewing. In Windows XP Professional, you can use Backup to back up the System State,
which includes the Registry, the COM class registration database, and the system boot files.
Registry Editor saves data automatically as you make entries or corrections. New Registry
data takes effect immediately. You can select Find Key on the View menu to search the Registry for a specific key.
Key names appear in the left pane of Registry Editor. The search begins at the currently selected key and parses all descendant keys for the specified key name. The search is local to the subtree in which the search begins. For example, a search for a key in the HKEY_LOCAL_MACHINE subtree does not include keys under HKEY_CURRENT_USER.
configuration settings can be made only directly through the Registry.
Caution Using Registry Editor incorrectly can cause serious, system-wide problems that
could require reinstallation of Windows XP Professional. When using Registry Editor to view or
edit data, use a program such as Windows Backup to save a backup copy of the Registry file
before viewing. In Windows XP Professional, you can use Backup to back up the System State,
which includes the Registry, the COM class registration database, and the system boot files.
Registry Editor saves data automatically as you make entries or corrections. New Registry
data takes effect immediately. You can select Find Key on the View menu to search the Registry for a specific key.
Key names appear in the left pane of Registry Editor. The search begins at the currently selected key and parses all descendant keys for the specified key name. The search is local to the subtree in which the search begins. For example, a search for a key in the HKEY_LOCAL_MACHINE subtree does not include keys under HKEY_CURRENT_USER.
