@roscopeco2000 To play FAF, you need to launch the game through the FAF client, and you need to have FA installed on your computer (most people install it through Steam because they own it through Steam), and, you need certain FAF versions of files like units.nx2 and ForgedAlliance.exe. The FAF client will automatically download the needed files for you when you try to join a game.
The file that is downloaded, called ForgedAlliance.exe, is different from the ForgedAlliance.exe file that is part of the Steam installation.
