Can't reinstall Arma 2 OA and update not working on Steam

I used to have the game installed perfectly fine and working until this latest update. It wouldn't let me update the game and kept stopping at around 98 or 99% finished. I tried deleting and reinstalling the game but when the installation finishes it automatically deletes itself apparently. Normal Arma 2 works and is installed just fine. Any solutions? I've heard other people have had the same trouble with updating.. Anyone with my problem? Thanks.