When you try to connect to the console session of a virtual machine (VM) that is running in Windows Server 2012 by using Microsoft System Center 2012 R2 Virtual Machine Manager (VMM 2012 R2) or Microsoft System Center 2012 Virtual Machine Manager Service Pack 1 (VMM 2012 SP1), the connection fails and you receive the following error message:
Virtual Machine Manager lost the connection to the virtual machine for one of the following reasons.
Another connection was established to the console of this machine
The virtual machine has been shut down or put into the saved state
The user credentials provided do not have the necessary privilege to connect
This problem occurs because connection access to Windows Server 2012 R2 hosts is controlled through a new method that uses the
command. In some cases, invalid user accounts in the member list for the Virtual Machine Manager user role can prevent the list from being populated.
For all the details and a resolution, please see the following: