How to perform Disk Cleanup on NTFS partition in windows

On an NTFS partition, Disk Cleanup can compress old files to save space. But calculating the savings and performing the compression often take a long time, and on some systems, Disk Cleanup hangs during the process. If that happens, or if

you don't care to wait, 

use this Registry tweak to disable the

  

compression: Delete the key

HKEY_ LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion \Explorer\VolumeCaches\Compress Old Files.