Try the following:
1. Type Regedit in Start - Run
1A. Backup the registry to a file
2. Navigate to
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVers
ion\Explorer\Volume Caches
3. Open "Compress Old Files" folder
4. Delete all files in this folder
5. Reboot
6. Run Disk Cleanup
This may work but it probably will just remove the step
from the routine.
You may have errors on your disk that it is having trouble
with.
Could try booting to a DOS prompt and run chkdsk /f c:
Good Luck!