Virtual Machines group cant be found for permission of VM
Hyper-V “Virtual Machines” Security Group Issue
The Hyper-V server role in Windows Server lets you create a virtualized server computing environment where you can create and manage virtual machines. You can run multiple operating systems on one physical computer and isolate the operating systems from each other. With this technology, you can improve the efficiency of your computing resources and free up your hardware resources.
Some of the major improvements to Windows Server 2012 are focused around Hyper-V. Here’s a deep look at some of the enhancements.
Virtualization: What’s new with Hyper-V
Microsoft Azure Web Sites Cheat Sheet
Shrink Virtual Hard Disk Image (VHD and VHDX) Files
23 best practices to improve hyper-v performance