I just tried to remotely control a server via RDP and got the error

The remote computer requires Network Level Authentication, which your computer does not support.

A quick search uncovered Microsoft KB 951608 which shows which two registry keys need editing to enable it. After you reboot of course.

• Click Start, click Run, type regedit, and then press ENTER.
• In the navigation pane, locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
• In the details pane, right-click Security Packages, and then click Modify.
• In the Value data box, type tspkg. Leave any data that is specific to other SSPs, and then click OK.
• In the navigation pane, locate and then click the following registry subkey: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders
• In the details pane, right-click SecurityProviders, and then click Modify.- In the Value data box, type credssp.dll. Leave any data that is specific to other SSPs, and then click OK.
• Exit Registry Editor.
• Restart the computer.

Now I’ve been able to connect to the remote site and get the job done.