I have Hyper-V (v6.0.6001.18016) running on host OS Windows Server 2008 x64 SP1 with a guest Virtual Machine running Windows XP SP3.
Suddenly, using Hyper-V Virtual Manager's "Connect..." option, I can no longer reach my guest XP VM (even though it is definitely running).
Here's the error message popup I get (jpg also attached):
Virtual Machine Connection:
This user account cannot access the virtual machine's video. If you this this is an error...
And on the console:
Check to make sure you are authorized to view this virtual machine's video
I also tried to RDP to it, but got a blank / black screen.