There is something called the "dirty bit" with an NTFS drive. If it gets set, the drive will run chkdsk the next reboot. It has been known to get stuck on. One of the ways to clear it, is to boot from an XP cd and use the recovery console. When you get to the console command prompt run chkdsk /p. This switch forces the volume to be checked for errors. I've seen it posted that this may need to be completed more than once to get it cleared.