Error: .... Vmount2.Vmount2Disk: Cannot open virtual storage driver. Make sure it is running..
I do not know what caused this, as was all working perfectly. However, a UNINSTALL, REBOOT, and reinstall of Virtual Center Server resolved this problem. Obviously something wrong with the vmount2.exe file, perhaps installing converter 3.0 on the same server?
A sidenote, trying to install without a reboot from the uninstall, resulted in the setup running through and then rolling back with the following error reported by service control manager in the system event log:
The Vstor2 Virtual Storage Driver service failed to start due to the following error: The system cannot find the path specified.
Anyhow, perhaps this may be of some use to someone.