Crusader54

I just tried to go through steam to do it, I went into properties then clicked the "set launch options.." button and typed it in there, I thought that is how you do it but then it didnt run anything at all, is there anyway you could quickly explain how to edit the shortcut?

I just did this and the GUIDs are different, is there any chance that since we are the same internet IP the server doesn't want a duplicate?

Ok, so this is somewhat hard to explain but basically I, Joe, purchased the Arma II CO game a few months ago and have been having fun with DayZ on both my Home PC and my Laptop, my brother recently noticed that the DayZ mod is awesome so he wanted to purchase his own copy of Arma II CO through Steam so we could play together, I assumed that the game would not run on the same steam account from two computers at once as that is the general rule. So we got him a copy and I had him run them both throgh steam once before joining in on DayZ, just as you would do if it is the first time you were to play the game, I didn't have him install it because it is already installed on the PC. The problem we are having is that while I, Joe, am playing DayZ on server X on my laptop, if my brother Sam, tries to log onto server X from the home PC, while he is on his own account for steam and everything, it will not work, but if he tries to log onto server Y then he joins fine. I think it has something to do with the servers thinking we have the same GUID, maybe we do have the same GUID, I am not sure. I hope that someone knows what is wrong here because I really don't want to just waste the $29.99 USD I just spent so me and my brother could play together. Thanks