Exactly, select Arma.exe, then "End Task" it till it shuts down. After that, I can start ArmA normally. Its weird because it only does it the first time I attempt to run it after I've re-booted. After that, as long as I don't re-boot, it fires up normally and evrything is fine and wonderful.
In my case, the problem is arma.exe appears in the task manager only during 2 seg. then it closes automatically without doing anything.