## Monday, August 22, 2011

### Workarounds For When “Add Virtual Hard Disk Wizard” Fails (Which Seems To Be All The Time…)

Adding new fixed sized VHDs using the Add Virtual Hard Disk Wizard in the Hyper-V console for some reason has stopped working for me on just about all my installs, with no errors logged. The VHD is created, but the progress slider bar never progresses and it will sit there, forever. It’s got to the point where I don’t use it and haven’t the time to debug the underlying cause.

A GUI-friendly way to work around this problem is to point Computer Management at the Hyper-V host and use Disk Management to Create the VHD.

Another way of doing this quickly is by using VHD Tool – although this doesn’t zero out the VHD and can leak information from the Hyper-V host and previous virtual machine’s disks into the newly created VHD. It is a great tool for lab work though.

Diskpart can also be used to create the VHD from the command line on the Hyper-V host. The command to do this is:

create vdisk file=”d:\path\to\file.vhd” maximum=<size in MB> type=fixed

UPDATE: So apparently I'm getting this error on networks where the domain controllers are still running Windows Server 2003 and an authoritative restore of Active Directory has been performed. The fix for this is to install MSKB 939820 on all the Windows Server 2003-based domain controllers in the affected domain. Interestingly I only found this trying to resolve a System Center Essentials 2010 installation.