I am having a problem with my CD-Key when I try to log in for multiplayer. When I enter my CD-Key I press ok and then I try to login. After entering my user name and password I press enter and it gives me a message saying that, "The CD-Key you entered is invalid." This occured after I reformatted my computer, but before I reformatted my computer, I could play everything. My previous operating system I have played on was Windows 7 Release Content and I reformatted to the same Operating System. I am assure that this game is compatible with Windows 7 and that nothing is wrong with my router. I can download this game correctly and everything, but it is just that it says my cd-key is invalid.