Viewport problem

I have recently upgraded to rhino 5 and all the viewports on my screen are 100% invisible or black. I also have rhino 4 on my system and have no problems with it. You can click anywhere on the 4 viewports and you can see in the command menu that it is doing something, you just cant see it visually in any viewport. Any ideas? I have a quad monitor system and i have never had issues with any other program not working. i have all the latest drivers installed for the video card.

I’m not certain, but I think maybe the case is that all viewports are actually closed somehow. Try running the ‘newviewport’ command.

Can you verify (options > View > OpenGL) that Rhino sees the video card and that it is using 'Accelerated hardware modes."?