How to Backup the Windows Registry
With the Windows registry being such a critical component in Windows operating systems, you would of course want to create backups of the Windows registry. The method that works in all versions of Windows is to use the File -> Export option in the Windows Registry Editor to save the contents of the selected key (including all subkeys) into a .reg file. The location of the export file can be selected, and the file can be copied to an external medium for safe keeping.
The Windows Registry Editor can be started by executing regedit with the Start -> Run command.
In Windows 2000 you can also make a backup of the Windows registry by creating an Emergency Repair Disk.
In Windows XP the easiest way to make a full backup of the Windows Registry is to execute C:\Windows\system32\restore\rstrui.exe (change the drive according to your configuration).
This will start the System Restore module, which allows you to create a restore point manually.
Simply select the Create a restore point radio button and click the Next button. Then type a Restore point description, and click the Create button. Wait for the restore point to be created and finally click the Close button.
In Windows Vista, the system restore feature is accessible from the control panel. First select System and Maintenance in the Control Panel. Next, select System. In the Tasks panel on the left-hand side, select System protection. Click the Continue button in case the UAC message pops up. In the System Properties dialog box, the System Protection tab will now be shown as the active tab.
To create a registry backup, click the Create button to create a new restore point. Enter a description for the restore point and click the Create button.
A third option is to use special registry programs that can be used to perform maintenance on the registry, including a backup. An example of a 3rd party program that can be used for registry backups only is Emergency Recovery Utility NT (ERUNT). This program can be used on NT, W2K, and XP, and is very simple to use. When you execute the program, it automatically asks you for a location to store the registry backup.
After you select the backup folder, and click OK, the program makes a backup of the registry. The backup folder will also contain a program file called ERUNT.EXE, which is all you need to restore the backup at any point in time.
ERUNT should not be used on Windows Vista as it was not designed for Vista, and the Vista registry is not exactly the same as the registry on earlier Windows versions.
Of course there are many other free and commercial registry programs that can be used to backup (and restore) the Windows registry.