Compacting a virtual hard disk reclaims unused space in the virtual disk. If a disk has empty space, this process reduces the amount of space the virtual disk occupies on the host drive.

Power off the virtual machine.

Verify that the virtual disk is not mapped or mounted. You cannot compact a virtual disk while it is mapped or mounted.

Verify that the disk space is not preallocated for the virtual hard disk. If the disk space was preallocated, you cannot compact the disk.

If the virtual hard disk is an independent disk, verify that it is in persistent mode.


Select the virtual machine and select VM > Settings.


On the Hardware tab, select the virtual hard disk to compact.


Select Utilities > Compact.


Click OK after the disk compacting process is complete.