what happens is the add/remove programs function is simply an easy way to access the uninstall that comes with the game, it can uninstall it by itself, so, if the uninstall file itself is gone, then add/remove cant remove it, but it still thinks the game is installed. you need to go into your registry and edit some files, namely the ones that make add/remove programs think Sins is still installed, but i would be VERY CAREFUL because if you delete the wrong thing you can screw up your computer, maybe find someone who knows specifically. i personally wouldnt try it on anyone but my own computer but if you are desperate drop me a pm
