Windows Registry

 

Key Components of the Windows Registry

1. Keys and Subkeys:

   • The registry is structured into keys and subkeys. Each key can contain multiple subkeys and values, much like a folder structure in a file system.

2. Values:

   • Each key in the registry can contain values. These values store the actual settings and can be of different types:
     • String (REG_SZ): Simple text.
     • Binary (REG_BINARY): Raw binary data.
     • DWORD (REG_DWORD): A 32-bit number.
     • QWORD (REG_QWORD): A 64-bit number.
     • Multi-String (REG_MULTI_SZ): A sequence of strings.
     • Expandable String (REG_EXPAND_SZ): A string that can contain variables that are resolved when the value is used.

3. Hives:

   • The registry is divided into several top-level sections called hives. Each hive contains a specific type of configuration information. The main hives include:
     • HKEY_CLASSES_ROOT (HKCR): Information about registered applications, file associations, and OLE object classes.
     • HKEY_CURRENT_USER (HKCU): Settings and preferences for the currently logged-in user.
     • HKEY_LOCAL_MACHINE (HKLM): Settings common to all users on the system.
     • HKEY_USERS (HKU): Contains user-specific settings for all users on the system.
     • HKEY_CURRENT_CONFIG (HKCC): Hardware profile information used by the local machine at startup.

Common Uses of the Registry

• Startup Programs: Registry keys control which programs start when Windows boots.
• Hardware Settings: Information about connected devices and hardware configurations is stored in the registry.
• Application Settings: Many applications store their configuration settings in the registry.
• File Associations: The registry determines which application opens a particular file type.

Accessing the Windows Registry

• Registry Editor (regedit): You can view and modify the registry using the built-in Registry Editor. Access it by typing regedit in the Run dialog (Win + R).

Important Notes

• Caution: Editing the registry can be risky. Incorrect changes can cause system instability or even prevent Windows from booting. It's recommended to back up the registry before making any changes.
• Backup: You can back up the registry or specific keys by using the export feature in the Registry Editor.