My son's Windows XP Pro system fails to boot properly. It boots up to the Windows screen, and then shows a BSOD briefly before restarting the boot process. I've checked all the hardware, and everything points to the hard drive. Western Digital WD40BB, NTFS, 1 partition, Windows XP Pro SP2 The system it is on, works fine with other drives and operating systems (DOS, 98, Win2000...) When I try to repair the disk, (Booting from the XP CD or in safe mode), the system fails after mup.sys (.exe?) Western Digital's disk utilities proclaim the disk is fine. I've put the disk on a working windows 2000 system, but when it gets to the boot banner screen, it hangs that system. Even though that drive is a slave. I'd rather not re-format and re-install all the OS and all the apps. Any help would be appreciated.