I just bought Outlaws off GOG.com because it's one of my favorite classics, I've got fond memories of playing it many years ago and it was only $6 so I figured why not. The game installs just fine and runs just fine, but the problem is I can't get past the first mission because when I get the brass key and take it to the second building/house and try to open the door it tells me "you need the brass key" when I already have the brass key! I even try switching to the brass key in my inventory and pressing enter to use the brass key on the door and it does the same thing! This is pretty annoying because I'd like to get past the first mission, but I can't because the game is telling me I don't have something that I clearly have right there in my inventory. I tried starting the mission all over again and it did the same thing.

Has anybody else experienced the same thing? Does anybody know how to fix this?

Never mind, I actually figured it out. Apparently the first brass key you pick up is actually the iron key and opens the iron door in the barn instead of the brass door.