Sometimes you need to fix Windows XP system files because they get corrupted after an excessive. But the real challenge is to repair or upgrade windows XP installation without losing personal data and files. When you repair a operating system, make sure you must backup all your data. You should also have the Windows XP serial key, a 25 digit alphanumeric code that validates your Windows XP.

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How to Repair and Upgrade Windows XP With the Help of an Installation CD