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You may lose data or program settings after reinstalling, repairing, or upgrading Windows XP
How to perform an in-place upgrade (reinstallation) of Windows XP

If you are not comfortable trying to reinstall or repair the Windows operating system, you might want to contact your computer manufacturer for help or bring your computer to a professional repair shop.
Reinstalling the Windows operating system or performing an in-place upgrade of your operating system is an extreme troubleshooting step...

A očito je takav potreban.
How to restore the operating system to a previous state in Windows XP