The Problem

A Windows 7 machine is showing a hard disk full error message on the desktop and there is 0mb left available on the hard drive. This prohibits doing many troubleshooting tasks as it stops most functions of control panel from opening because of the limited space.

The Common Culprit

Under C:\Windows\Temp there are a large number of automatically generated .CAB files. If you try and simply delete them, upon a reboot Windows will begin to automatically generate them causing the storage drive to fill up again. There is a good explanation HERE as to why this happens. 

The Solution

  1. First go to C:\Windows\Logs and delete the oldest .LOG file in this folder. You can also delete all of the log files as they can also be large in size.
  2. After deleting the .LOG file, navigate to C:\Windows\Temp and proceed to delete every single .CAB file in there. This will take time depending on the number of the .CAB files.
  3. Empty the recycle bin to completely delete the files.

This should solve the problem and stop it from happening again. If you look at the C:\ drive in the file explorer now, it should show much more free space than before.