I have two drives used for SQL backups which for the last week have been acting strange - the free space indicated by windows is far off from what windirstat, etc indicates. There should only be about 60 GB of drive space used and there is about 160. This would match the utilization if the two last backup files were still residing on disk.

SQL server is 2000, OS Server 2003 x64. Running on a VMware 5.0 cluster. OSSEC and McAfee for this system shows clean.

My current plan is to temporarily attach one of these drives this drive to another VM for analysis. Is there anything more I should be looking at? There were a lot of pages on the net when I was looking for documentation on this issue but I haven't found this case described.

EDIT:

Unfortunately even a full reboot did not clear this behavior. I also used process explorer to look for open file handles. No dice.