Yes, I know, but yesterday i purchased Arma 2: Operation Arrowhead from Bohemia, but it is a stand alone game. It is not Arma 2 as well. So, my question is, can I just purchase Arma 2, install it, and play Day Z, or does Day Z require specifically the Combined Operations install? What is interesting is the OA stand along game is installed in an Arma 2 folder, and not an Operation Arrow folder like I see in some of the posts. I just want to know for sure before I purchase the original Arma 2 that it will work. Thanks!