nexarhd

Hi, I have looked and looked for a solution and I had to try this myself to save downloading around 15GB, my brother had Arma 2 Combined Operation on a Retail copy of the game and you can Install Arma 2 & Operation Arrowhead on steam with the disk. all you have to do is just make a few alterations when installing the disk, make sure that you start autorun and put in your steam that you own it on, or the CD key inside your case just install it to your steam common directory just keep the file name the same and take out where it say's BohemiaInteractive and install, now all you have to do now is to press the install button in steam and it will detect that there is Arma 2 in your steam game you just have to download an extra 2-3GB of the game to work on steam, then you can play.