This is a Hypervisor 101 case that keeps showing itself every so often the forums, mailing lists, etc: A message to the effect of “The Hypervisor is not running” when a user tries to launch a VM. Felipe Ayora, one of our awesome UA people, has created this video that steps through how to investigate such a failure and fix it

<a href="http://www.microsoft.com/video/en/us/details/25d07f2e-b