How come my Windows 7 does not validate as genuine when I bought it from Packard Bell website?

Q: I have been trying to make a movie with windows live movie maker and when I try to burn it my computer shuts down. I asked for help and was told I needed to validate that I was using a genuine copy of windows 7. I bought the computer three months ago with windows vista and paid for the upgrade to windows 7, when I tried to validate it I was told that it was not a genuine copy. I got it from the Packard bell website so it should be good. could I be having a problem because I downloaded a language pack to change the language from Italian to English?