I've been able to reproduce this on two separate hosts (both Win 8.1 Pro) running Gen 2 Windows Server 2012 VMs. I believe it is after the December 2012 round of updates (and I'm trying to confirm which specific one), the VMs fail to boot, indicating that applying a patch failed and it is reverting the changes -- it enters a reboot loop which I'm unable to get out of.
Has anyone else experienced this with Gen 2 Server 2012 VMs?
Trevor Seward, MCC
Follow or contact me at...
  
This post is my own opinion and does not necessarily reflect the opinion or view of Microsoft, its employees, or other MVPs.