Your copy of the game will be added to your Steam Library. Once added, you will be able to download and play the game from Steam Library.
Please note that your CD key will remain the same, you will not get a new copy of the game this way - your current copy will be transferred to Steam.
If you do not have Steam installed, please follow this link to download and install it.
Click on the Games tab in the menu in the top of the client.
Then select Activate a Product on Steam from the menu.
Click the Next button until you get to this screen:
There you can enter your CD key.
Then click Next again. Your game is now activated and you can download it the same way you download any game on Steam.
Please note that this will work only for Arma 2, Arma 2 Operation Arrowhead and all Arma 2 DLCs. Also, you can only activate your game on an account where the game has not been activated yet.
In case you exceeded your activation limit, please send us your CD-key and BIstore account name or registration email.
You can also activate your CD key on Steam. There is no activation limit for Steam version of the DLC.
In case of a re-activation, you need to use the same email address you used when activating the game for the first time.If you cannot remember the email you used, please contact our support.
In case of first-time activation, your internet security programs are probably blocking the on-line licensing process. Please disable your firewall, anti-virus and anti-spyware programs. Also, make sure you are running the PMC setup with administrator rights and that you have the UAC (User Account Control) turned off in Windows Vista/7/8.
You can also activate your CD key on Steam. There is no activation limit for Steam version of the DLC.