Rhino Renders black (with V-ray)

Hi Guys
I am kind of new to rhino and vray. When I click on vray render after assigning material to my furniture in rhino, the render appears completely black. I checked the GI (Global Illumiination) and it is turned on. I still get a render that appears completely black. Can someone please help, what else should I check ?
Appreciate any help i could get

You could press the “Revert to the default render settings” button at the asset editor. This reset the global settings. Now if you press the render button you should see the default background and the objects at your scene. Is this working? If not, open a new scene and create a simple object like a cube - do this work?

What version of V-Ray/Rhino do you use?