Windows Server – Clean DEDUP after remove files

Tip: Free space after a lot data has been deleted/moved from a Windows Server 2012 (R2) volume with enabled deduplication

On some volumes there is deduplication enabled and after i’ve moved a bunch of data away from these volumes to free diskspace the Windows Explorer still shows no “new” free space available. By default Server 2012 and R2 will free diskspace one time per week or with other words you will not get free diskspace by only deleting a file; quite simple.

So how can you force Windows Server 2012R2 to free the diskspace asap? Quite simple, start the PowerShell as Administrator and run the following command:

Start-DedupJob -Type GarbageCollection -Priority High -Volume d:\

After you start the job you can check the status with


Wait until the job is finished and check the free space again, it should be available now. I will not explain why deduplication is working in this way here but I did note sometimes Administrators are not aware about the way how it works and that’s the reason why i mention it here.