Windows vista/ win7 upgrade clean install

jonno208

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Jul 25, 2009
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Hey guys, On my old pc I have Windows 7 which I upgraded from windows Vista. I no longer have the vista disk(I think). Is there anyway to wipe and reinstall win7 with the upgrade disk? Or any other way I can do a clean install without buying a new copy of win7?(Legally plz :D)

Edit: The reason I am doing this is I might give it to a friend once I get my new build in a month or 2