Try these steps:
1.Logon to the server locally
2.Click Start, Run, type "tscc.msc /s" (without quotation marks) and click OK
3.In the Terminal Services Configuration snap-in double-click Connections, then RDP-Tcp in the right pane
4.Click the Network Adapter tab, select the correct network adapter and click OK
5.Make sure that you can establish an RDP connection to the server
The change takes effect immediately. No need for a restart.
Source:
http://social.technet.microsoft.com/Forums/en-US/winserverTS/thread/37299e00-9e61-4154-8d42-1dc6d7b6cdd1/[
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Other resource:
http://windows.microsoft.com/en-US/windows-vista/Troubleshoot-Remote-Desktop-problems[
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