Invalid CD key

[Lord]

I have been playing Halo for a long time without any problems, and Halo CE has been working fine too. All of a sudden it says "Invalid CD key" EVERY time I try to join a game...whats going on? Did someone get a hold of my CD key?

[D3V0N]

Like any other game if this happens and you bought the game. Contact the creators of it and ask them what you can do, they may make you send in the old and send you a new box and everything.

[SpartanV]

damn, i had cleared my hard drive and when i went to install halo again i lost my cd key. is there any way to find another one that will work? where can i find it.

[Duffman]

contact microsoft. They'll ask you for your cd-set and then they'll send you a replacement disk