I'm running windows 7 ultimate 64Bit. After installing Win XP on my second drive I received an MBR ERROR 3. I booted Win 7 repair disc and ran it several times. Rebooted my computer (while repair disc was in the drive) I got windows dualboot screen and was able to access XP & WIN7. Here is the WEIRD PART... IF I BOOT WITHOUT THE REPAIR DISC IN THE DRIVE, I get an MBR ERROR 3. Has anyone seen anything like this before??? I'm stumped! Can anyone help..