This is definitely not a UAC issue. The first thing I do when setting up a computer is to permanently disable UAC. It's the silliest invention in mankind.
But to give an update on the issue, I got around it by:
- Defragmenting/consolidating free space on the Windows drive
- Reducing the disk size in Windows
- Connecting a QNAP NAS to vSphere and then copy the VM to the other datastore (just in case)
- Creating an additional disk in the VM
- Cloning the disk with Ghost, reducing the disk in the process
- Deleting the original disk
- Copying the VM back to my main server
Took me a weekend, but it's all good now!
- Ivar