As the title states, i ran out and bought the game lanch day, only to be not able to freaking PLAY the game! I googled the problem, and saw that there were reports of a Key-Gen that spit out legit keys. I am suspecting this could have been the problem, that maybe someone already generated my key! Even if i cant play multiplayer for a while, till then, atleast let me get into story mode while things are sorted. But I cant even get past activation! PLEASE HELP!

make sure your putting dashes in the cd key when u enter it and all caps but your not the only one with these issues it seems there is a growing group of players that cant connect to servers in multiplayer as our "serial keys are in use", also some ppl are having probs with antivirus picking up on the Crysis2.exe and Crysis2launcher files or maybe they really are viruses and crytek is planning on robbing us all blind once we have the game installed, lol, dirty rotten scoundrels.

I am having this same problem. Single player works, but when I try to play multi-player and join a server, I get "serial code already in use."

Very frustrating.

I am having this same problem. Single player works, but when I try to play multi-player and join a server, I get "serial code already in use."

Very frustrating.
This is actually a very common problem, i think it has to do with the amount
of people trying to activate there game at once.

I cannot even play single player. I would like to play Campaign atleast, but activation fails when the game starts, and tells me that I have an invalid key. Ill give this matter until the weekend to settle, and if no change, I am returning this game.

Yet another person here who is being told my CD key is in use. Seriously guys, this is ridiculous. Is there a support forum somewhere that deals with this stuff? Can we get one of the Cry-"staff" to respond here?

just another voice confirming entered in a alters CD key like other people suggested, and it worked. no troll, just wanna have the world know how **** their game and support are