Why did you reimage? If the system was sluggish, you probably have bad blocks on the hard drive that need to be repaired, or your best bet is to pay the $150.00 for a new hard drive and reimage. We are running into this across the board, but it's not a bug error, just the lifecycle of a scsi hard drive.
Not a big deal if you have a backup. Most of our customers understand about the life of a hard drive.