Stupid copy protection. I made an image of one of my old game CDs and mounted it on my HD as a virtual CD drive, but the game won't recognise it, so I'm having to stick to the real CD and CD drive. The game slows down a lot while the CD drive whirs about trying to find the needed data and it keeps crashing when the CD drive isn't fast enough or there's a fleck or dirt or something. One more reason for why pirating is the way to go.