Why does

My Oblivion game play fine when my hard drive isn't attatched, but when I re-attatch my hard drive, the game no longer works and I get a disc read error? What the ****? I've deleted all the saves from the hard drive and still no luck. Anybody know a solution?

Try wiping off the disc, it might help it. Take a soft cloth, dampen it, and wipe from the inside of the disc outward in a straight line. This is a weird problem, maybe you'll get lucky and it'll work after this!onehardrocker