What do I need to keep?

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what files in the program files folder do I need to run xp? I want to delete everything but those.

[Dwarra?]

Format your hard drive

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Format your hard drive

How do I do that?

[:)]

do you have your XP disk?
is your computer by any chance store bought? if so do you know if it had a revert system? (if its dell i'm pretty sure it does, also some other company's have them)

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store bought Compaq presario, came with XP.