Make XP Genuine

download jellybean keyfinder from this website

http://www.magicaljellybean.com/keyfinder.shtml

Now open keyfinder.exe
Click on options and click "change windows key"
Now enter this key and you're done.
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V2C47-MK7JD-3R89F-D2KXW-VPK3J
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P.S: this works on windows xp pro and home sp2 only......