When the registry entry described below is added then RDP connections using
AD credentials fail with "RPC Server is Unavailable" error  Also a 1219
Winlogon entry is generated in the server Application Log.  The details on
that are:  Logon rejected for Domain\Username. Unable to obtain Terminal
Server User Configuration. Error: The RPC server is unavailable.

I can log onto this server using local admin credentials but not the domain.
This registry entry is also on other domain servers and there are no logon
issues.

I've tried a number of things including checking network adapter
configuration, provider order, rejoining the server to the domain, and also
asking the network team to run traces.  I have no idea at this point why this
is failing. Any ideas???

http://support.microsoft.com/kb/301673
This fix applies only to the SMB protocol traffic over TCP NetBIOS port 139.
The connectivity problem that is mentioned in this article still occurs on
client computers that are running Windows 2000 or later if you make the
connection with direct hosting on port 445. By default, Windows 2000 uses
this port.

You can establish no more than one direct hosting client connection across a
NAT device. If you must have more than one simultaneous SMB protocol, disable
either direct hosting on the Windows 2000 file server or on all clients
behind the NAT device.

To disable direct hosting on the server:
Start Registry Editor.
Locate and then click the following registry key:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\NetBT\Parameters
Add the following registry value:
Value Name: SmbDeviceEnabled
Type: REG_DWORD
Value Data: 0

The default setting is 1 (enabled)

When you complete these steps, clients must use port 139 NetBIOS over TCP/IP
to make a connection.

Bill <B***@discussions.microsoft.com> typed:

Try starting the Remote Procedure Call (RPC) service and setting it to
"Automatic".

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