Thursday, July 7, 2011

Hyper-V - Failed to Power on With Error ‘General access denied error’

This error is common when doing manual disk swaps with a disk that hasn’t been used by this Hyper-V host. Hyper-V applies permissions to each VHD with only the required rights apon adding them. This only becomes an issue if leave the disk in the virtual machine configuration and swap out the VHD file.

This is the error that comes up when attempting to start the virtual machine.

VM Perm Deny

After checking the VHD file permissions you will notice only the default inherited permissions are there.

Permissions Missing

To fix this is as easy as removing the VHD that was swapped out from the virtual machine configuration.

Remove HD

At this point just after saving the VM configuration reopen the configuration and add your VHD file again and save it.

Add HD

Check your file permissions on your VHD file that’s now attached to your VM and you should see a SID of the service account.

Permissions Added

Go ahead and start your VM and all should be well and boot. I hope this helped someone from extra effort.

On a related note to this post play with virtual machine manager if you already haven’t.