Hi..Thanks ..After creating more space on the fullest drive, I've discovered that drive is OK..It is the drive with 50% free space that is the problem. Diskeeper won't work on it. But it's only slightly defragged anyway. What is the RAID 1 mirror set? What should I do next?..Seems like Drive G: is locked up in some way...CHKDSK is fine on it. The drive is a Seagate Barracuda ST3500630AS SCSI 500GB. Thank You. CZ