yea that happen to me and a couple of other members in my clan..weird its going around..what i've figured out was my cd key was not in the registry even though i inputed the # (i did a full uninstall to fix a corrupted file cuz the repair didnt work) when i check to if my cd key was there it was a hell of alot of #'s u have to modify that cd key and add ur orig. key back into ur registry, its should take a couple of games for ur new guid to stick..mine is now working fine