My server came from dell with a 40GB OS Boot c: drive, and I needed to make it larger. While trying to extend the partition in server manager –> file and storage services, I was receiving the following error “error extending volume: size not supported”.
My server came preinstalled with a C: drive and D: drive, in order to extend this drive I had to delete the D: partition. However once deleted everytime I would try to extend the original C: it was coming up with “error extending volume: size not supported”.
Windows Server 2012 error extending volume: size not supported
There wasn’t very post on this subject (like 4) but I did find a suggestion, and it worked for me.
If you go to Administrative Tools –> Computer Management
You get the console we are all used to since Windows 2000 Server. The one you used to get when you right clicked and selected manage on “My Computer”.
Once there, the old disk manager is still there. I found that while the drive was deleted from the server manager, the partition was still there.
I deleted the original partition, and then was able to extend the volume.
If this helps you please leave a comment below. if you post something intelligent I will approve it.