Using the export function of Registry Editor is a great idea prior to making any Registry edits, but far from the only option to restore previous settings if something goes wrong. For example, you could also create a restore point using System Restore in Windows XP or ME prior to making Registry changes, since the restore point will contain your current settings.
Along the same lines, Microsoft does not recommend using Registry Editor as the primary method of backing up and restoring the entire Registry in XP. Instead, you should use the Backup tool, to both backup and restore what is known as System State data. System State data include the Registry as well as important system files, however, so the backup is typically much larger. However, it is a more reliable way to handle Registry backup and restore operations. If you’re running XP Home edition, the Backup utility is not installed by default, but is included on the XP CD. See the stepped procedures below for more information on installing the Backup utility and backing up System State data.
Step 1: Backup is not installed on XP Home by default. Insert your XP CD and browse to the \valueadd\msft\ntbackup folder. Double-click on the NTBACKUP.MSI file, to begin the installation. Once the automated installation is complete, click Finish.
Step 2: Click Start, and then select All Programs, Accessories, System Tools, and click Backup. The Welcome to Backup or Restore Wizard window will appear. Click Next.
Step 3: At the Backup and Restore screen, ensure that Back up files and settings is selected, and click Next. At the What to Back Up screen, select Let me choose what to back up, and click Next.
Step 4: At the Items to Back Up screen, expand My Computer, and click on System State. This will display the components included in a System State backup, including the Registry. Check the checkbox next to System State, as shown above, and then click Next.
Step 5: At the Backup Type, Destination, and Name screen, click the Browse button to choose a folder where the backup should be saved. In the backup name text box, give the backup a descriptive name such as SystemStateJuly0606. Click Next.
Step 6: On the Completing the Backup or Restore Wizard screen, click Finish. The Backup Progress window will appear. Once the backup is complete, check the location specified to ensure that the System State backup file specified exists.