I've had CoD since it became avaliable in my town and MP worked just fine, it worked perfectly yesterday, now I cannot get in because it says I have a bum CD key mad:

the only thing I can think of is I was hacked by the immature prick of a TKer I kept vote-kicking on a server yesterday, but I don't think the immature prick has even close to the level of skill necessary to pull this off, so that is not likely.

Anyone got ideas?