I use Remote Desktop (RDP) almost every day, on two Windows 7 Pro machines (my desktop and laptop). Today RDP just stopped working, and I'm not sure what caused the problem. Here is someone else's screen shot of the error message.

After Googling a bit, I found a discussion on Microsoft TechNet. One of the last suggestions pointed me to a solution that solved my problem. It does require editing the Windows registry, and required me to add a missing DLL reference.

Configure Network Level Authentication

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

Last modified: August 16, 2013