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Windows Hyper-V-Server

Server Manager: Hyper-V tab shows Access denied: Unable to establish communication between Client and Server

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After having successfully added a server to Server Manager, on the Hyper-V tab the following message is shown against the server:

The Solution

Whilst most "access denied" errors indicate that the server is rejecting the client, in this case the error is caused by the client's configuration.

Steps to resolve this problem:

1. On the client (i.e. the computer on which you are running Server Manager), open up a command prompt.
2. In the command prompt type:
   DCOMCNFG
   This will open up "Component Services".
3. Expand Component Services → Computers
   you should then see "My Computer"
4. Right click "My Computer" and select "Properties"
   note: don't simply double click it as that will expand it without opening its properties.
5. On the "COM Security" tab, under "Access Permissions" click the button [Edit Limits...]
6. Select "ANONYMOUS LOGON" and check the allow option for "Remote Access".
7. Close the dialog by clicking [OK] twice.

Once you refresh the Hyper-V view in Server Manager you should see that the "access denied" message has gone.