RDP to Server Drops after Authentication or even earlier

This one's made me crazy - 

Server 2008 R2 Standard Running as a virtual on Hyper-V  This is the only server of many that exhibits this issue:

1) From A Windows 7 PC - attempting a Remote Desktop Connection, one of two things will happen:
    - Authentication happens, and then the session will drop (While the blue "Welcome" screen is up, -or- 
    - Remote Desktop will come back and report - "unable to establish a connection."

2) I can RDP into the Host Server and connect to the culprit using the Hyper-V console just fine.

3) Remote settings on the culprit are enabled to allow connections from users using any version of RDP

There are no errors logged in Application, Security, or System at the time of the failed attempt.  If thee system would even leave me a trail of bread crumbs, I would feel better.

Any ideas or places to look will be greatly appreciated!