So, I reformatted my pc last week, I deactivated c2 first from my pc.
Today I re-installed c2 and when i go to multiplayer it says "serial code currently in use".

This usually happens after a patch but usually I skip the 1st log in page then click mp and then log in and all is well but that workaround won't work this time.

Any idea's will be appreciated,
cheers.

Thanks for deactivating, I was banned and out of the blue moon, I had some luck to be able to phish your account serial #

lol, okay in all seriousness, this has not happened to be so far. I've reformated my computer at least 3 times now ever since the game came out, and it has been working perfectly fine every time I reformat.

What patch version were you on when you were trying to log-in?
You should search the forums and see what methods other users have used

I'm on 1.9, I am gonna try re-installing.

So, I reformatted my pc last week, I deactivated c2 first from my pc.
Today I re-installed c2 and when i go to multiplayer it says "serial code currently in use".

This usually happens after a patch but usually I skip the 1st log in page then click mp and then log in and all is well but that workaround won't work this time.

Any idea's will be appreciated,
cheers.

Did you try logging in when you get in the game, then go to Multiplayer? Also try changing your CD key below (below logging in there should be an option to change your CD key), but don't change just type the same one... Btw. You must be sure, that you typed everything correct!

Lol, this game is very highly strung.....I just tried loging in one more time before i re-installed and it logged me in no problem.
I did the skip 1st log in screen then mp then log in and it worked.

Thanks for your suggestions guys/gals.

Well don't know for sure so please keep us informed if you get it figured out. But here is an idea of what MIGHT have happened. Most serial coding systems work on a system of serial or serials that have to be correct to be accepted by the software. Software companies knowing that it is relatively trivial to map out the way that codes are checked by the software and verified as being of the valid format, have gone ahead and put an additional check. They come up with a schema of generating the serials that will more than cover the number of possible serials that they ever expect to have. They then put genuine serials which go with a retail or purchased product into a database which is checked against over the net as a way of determining if a serials of the correct format is indeed a serial that was tied to a product sold. I don't know the way keygens for Crysis 2 work, but it is possible someone using a keygen just happened to get your exact serial generated. Hence your key was in use. Or it could be just a software error where a session that contained your serial was never cleared out for some reason. Pirates usually just create a modified binary .exe or dll that simply jumps around the code which would check such things, but in the case of programs that require an internet connection and do a verification of those binary files to make sure they have not been modified pirates may simply resort to mass generating keys and seeing which one sticks when they throw it at the wall. I would suggest you contact EA or Steam and inquire about this to see what IP/session they have showing that particular key is in use. Maybe its a software error they can clear, maybe its a pirate who just happened to land on your key. If it's the pirate they should be able to see that your key is in use from different IP/session/hardware GUID, remove that key from the database of accepted keys, and generate you a new one. I'd imagine they'd only do this once if ever so if your key became exposed due to your machines/accounts falling victim you'd be up a creek as far as getting your issue resolved. Like I said good luck