1, what hack did u actually use.
2, what do you mean, is it a cracked version or?
If it's cracked it could be that, or maybe the injector ( if u used one ) is not working, or the hack is patched/don't work for you and it may not work for vista..
you can give me more info b answering those 2 questions, make sure the link u give my for the hack is on mpgh.net if it isn't don't bother.