In may 2010 I got a hand-me-down computer from my brother and wanted to wipe his old data to get more sapce on it. I wiped it and put in my old disk a vista one and it wouldn't read it. So I go on Ebay and buy a Windows 7 Ultimate for $30 and activated it. About a month later My motherboard got fried and I got it replaced with the same motherboard and when I log on it says my copy of windows is not genuine and have to buy a new copy of it. Why is this? It said the key was authentic when I used it but not it says its fake? Any way to fix this other than buying a new copy of it?