Windows® XP Professional and Home Edition
Windows® XP does start
Log on to Windows® as Administrator.
To restore the registry to one of it's previous states, you can use either the Start Menu -> Registry First Aid group -> Registry restore shortcut or run the System Restore utility from the All Programs -> Accessories ->System Tools menu.
System Restore starts. On the Welcome to System Restore page, click "Restore my computer to an earlier time" (if it is not already selected), and then click Next.
On the Select a Restore Point page, pick a date on the calendar, select in the restore point list the most recent system checkpoint created with the program, and then click Next. A System Restore message may appear that lists configuration changes that System Restore will make. Click OK.
On the Confirm Restore Point Selection page, click Next. System Restore restores the previous Windows® XP configuration, and then restarts the computer.
Log on to the computer as Administrator. The System Restore Restoration Complete page appears.
Click OK.
For additional information about System Restore in Windows® XP, click Help and Support on the Start menu. In the Search box, type "system restore", and then press ENTER.
Windows® XP does not start
If Windows® does not start, restart Windows® by using the "Last Known Good Configuration feature": start the computer and then press the [F8] key when Windows® begins to start. The Windows® Advanced Options menu appears.
Use the ARROW keys to select "Last Known Good Configuration" (your most recent settings that worked), and then press [ENTER].
If a boot menu appears, use the ARROW keys to select Microsoft Windows® XP, and then press [ENTER]. Windows® XP restores the computer to the most recent restore point.
To run the System Restore from the Safe Mode do the following.
Boot into safe mode, log on with an administrator account privileges and type into the command prompt:
%systemroot%\system32\restore\rstrui.exe. Then press enter.
Warning! Make sure that your backups are current. If you restore an old backup it could be fatal if you've made major changes to the operating system or hardware since the backups were created. For example, if you've installed Internet Explorer 6 and restore your registry from a backup predating that, expect that your computer won't boot properly.