Hi! Can anyone help me with this problem?

I have MTW VI v.2.01, and I've tried to log onto GameSpy to play the multiplayer games. I have a previous user name and password on GameSpy for another game, but every time I try to log on, it tells me my CD key is invalid. Since I own Battle Collection, I have two CD keys, one for MTW and one for VI. I have tried both and both were "invalid". Could this be a case of someone "stealing" my CD key and the CD key being blocked, or do I need to register my CD key first and where?

Help would be appreciated.

Marquis de Said