How to uninstall Windows XP SP 2

This is for all my PC friends. I woke up this morning to an error dialog on Trisha's computer telling me that after auto update had tried to install Windows XP SP2 the computer would no longer boot. So, if you are installing SP 2 and it fails, leaving your computer unbootable, here is a fix using your XP disc...

How To: Uninstall Windows XP SP 2 using Recovery Console:

Please note: If the computer cannot start in either Normal mode or Safe mode, then the Service Pack 2 removal can be started through the Recovery Console.

1. Turn on the computer with the Microsoft® Windows® XP disc in the CD/DVD drive. When prompted to start from the CD, press any key. If you miss the message and arrive at a blinking cursor, restart the computer and try pressing any key again when the message appears.
2. Windows XP Setup prepares to run. If you need to install a third party SCSI or RAID driver, press the F6 key during startup.
3. The option for an Automated System Recovery appears momentarily.
4. Setup loads the files necessary for the installation, and then starts Windows.
5. Press the R key to run the Recovery Console for Windows XP.
6. Press the number for the corresponding Windows installation for which you know the administrator password. (For most users this will be 1)
7. After selecting the appropriate Windows installation, type the administrator password when prompted.
8. The screen displays a C:\WINDOWS prompt.
9. At the C:\WINDOWS prompt, type: cd $ntservicepackuninstall$.
Press the ENTER key.
10. At the At the C:\WINDOWS\$NtServicePackUninstall$ prompt, type: cd spuninst. Press ENTER.
11. At the At the C:\WINDOWS\$NtServicePackUninstall$\SPuninst prompt, type: batch spuninst.txt. Press ENTER.
12. The batch file manually removes Service Pack 2 from the computer. This process takes several minutes.
13. At the C:\WINDOWS\$NtServicePackUninstall$\SPuninst prompt, type: Exit. Press ENTER. The computer restarts.
14. From the Start menu, click Run. In the Run dialog box, type:
Regedit. Click OK.
15. Locate the following registry key:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\ServicesRPCSs.
16. In the right pane, double-click ObjectName.
17. An Edit String dialog box displays. In the dialog box, type:
Localsystem. Click OK.
18. From the File menu, click Exit to quit Registry Editor.
19. Restart the computer.
20. Open Control Panel. From the Microsoft® Windows® XP default Start menu, click Control Panel. From the classic Start menu, point to Settings, and then click Control Panel.
21. In Control Panel, open Add or Remove Programs. If you are in Category View, click Add or Remove Programs. If you are in Classic View, double-click Add or Remove Programs.
22. In the Add or Remove Programs window, select Windows XP Service Pack 2, and then click Remove.
23. In the Windows XP Service Pack 2 Removal Wizard dialog box, click Next.
24. Service Pack 2 inspects the configuration, checks for necessary disk space, stops services, restores catalogs, and then runs processes before removal.
25. The computer deletes installed SP2 files and copies backup files to the hard drive.
26. In the Windows XP Service Pack 2 Removal Wizard dialog box, click Finish to restart the computer.


Note: If removing the Service Pack 2 through Recovery Console does not properly work, a repair installation of Windows XP will restore the original Windows XP files.