This a registry editor error on the Windows 7 operating system. Please complete the following steps:-
Right-click your Start button and choose Run (or press the Windows key + R)
In the Run window type regedit and press OK
Browse to the following key: HKEY_CURRENT_USER\Software\Microsoft\Terminal Server Client
Highlight/select the "Terminal Server Client" key/folder
On the right hand side, right-click an empty area and choose New, DWORD (32-bit) Value
Name this field: RDGClientTransport and give it a value of 1
Press OK, exit the Registry Editor and try logging into the server
