Windows Server 2008 R2 not showing all available free space and won’t extend
We recently had an alert come through regarding one of our customer’s data drives running out of space. I logged into to vCenter and extended the VM guest’s data drive, logged into Windows, ran DiskPart, selected the volume & extended it. This is generally my preferred method as more often than not it doesn’t show the space in Windows Explorer when the same process is ran from Disk Management.
The extend showed that it completed successfully and all the available space showed up in Disk Management. However it still wasn’t showing in Windows, even after a restart of the server. Next thing I ran was extend filesystem on the selected volume. This came back with the following error: DiskPart has encountered an error: The device does not recognize the command. See the System Event Log for more information.
Researched the issue further and noticed that the Volume Shadow Copy Service was started, although there were not any scheduled Shadow Copies or Shadow Protect backups currently running. Stopped the service and re-ran the extend in Diskpart – this time it completed with no errors and the correct space was then shown in Windows.