When you open Disk Cleanup it gets stuck on ‘System Error Memory Dump Files’
Click Start and type regedit into the search box.
Navigate to:
“HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\VolumeCaches\System error memory dump files”
The “Flags” value must be set to “0″.
Or for 64-bit Windows:
“HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows\CurrentVersion\Explorer\VolumeCaches\System error memory dump files”
The “Flags” value must be set to “0″.