I had the same problem. I don't remember how I fixed it.Well I have a situation similar to yours but I didn't uninstall my bg2 my so dear cousin 'deleted' it and I can't reinstall it my fried says that it has something to do with the dll files in the windows folders how can I reinstall it?
PS: I can't uninstall it either from the control panel I tried and it said that bg2 was already uninstalled.
PS2: I reported this message accidently... sorry...
