It would, but when you register with m$, they keep a registry of them, so if you have a copy and try to get it registered, m$ will know because the original was already registered. To get around those who get it regd first before making a copy, thats why windows update checks it too. Of course, corporate versions work differently, multiple copies are allowed, so if you can make the small? change, you will be able to legitimise your copy.