Ensure that the Windows Remote Management (WS-Management) service and the VMM agent are installed and running and that a ...

Ensure that the Windows Remote Management (WS-Management) service and the VMM agent are installed and running and that a firewall is not blocking HTTPS traffic. 

This problem can also be caused by antivirus software that is installed in the parent partition of the virtualization server (%ServerName;) if the real-time scanning component is configured to monitor the Hyper-V virtual machine files. For more details on how to resolve the issue look into KB 961804, http://support.microsoft.com/kb/961804. 

If the error still persists, restart the server (%ServerName;), and then try the operation again.