Unmoveable files when shrinking your C: partition on Windows 7

You can shrink partitions in “Computer Management” – “Disk Management” on Windows 7. (You can find this in “Control Panel” – “System and Security” – “Administrative Tools”.) When you right-click your operating system partition and choose “Shrink Volume…”, the available shrink space is being calculated. The available shrink space does not only depend on the amount of available disk space on this partition, but there can also be some unmoveable files that prevent you from shrinking the disk space more than a certain amount.

On my new DELL computer, I could only shrink the disk to half it’s size (150 GB), while only 20 GB was used. Also defragmenting the disk did not help.

After the “Querying Shrink Space” has finished, you can see which unmoveable file is responsible. To do this, you need to go to Event Viewer (which you can find in Computer Management as well). You have to go to “Windows Logs” – “Application”. You will see 2 entries in a row for which the source is “Defrag”. The second one gives the information you are searching for.

On my computer, the message says: “The last unmovable file appears to be: \System Volume Information\{f94d9e25b-4217-11df-9570-005056c00008}{3808876b-c176-4e48-b7ae-04046e6cc752}:$DATA

I found out that this file is part of a System Restore Point. You can remove the file by disabling System Restore. (You can enable it again and create a new restore point after shrinking your disk space.) To disable System Restore, you should go to “Control Panel” – “System and Security” – “System” – “Advanced System Settings” – tab “System Protection”. Click on the drive for which you want to disable system restore (probably your C: drive) and click “Configure…”. Now choose “Turn off system protection” and click Apply. Hopefully there are no other unmoveable files which prevent you from shrinking your disk drive to the prefered size.