SDK not working. Pages blank, options greyed out.

My issue is that when I launch the SDK I get "Remote server returned an error: (404) Not Found."

Then there is nothing in the Getting Started or the Community page tabs, they are blank. And the Samples page lists the available project samples but all the choices are greyed out. At the bottom it says "Not Licensed."

Does anyone know how I get the SDK licensed or working? I don't see any place in the SDK software to enter my project license. The project and license are successfully set up in the Sitefinity Project Manager.

Please help...
Tien