3ds Max: A problem about material preview in viewport

When I am using materials from plugins such as Vray, brazil, etc

once i apply them to a object, the object turn to a full black

i can not even preview the diffuse color on it unless render it

It's really boring i feel

how can i get rid of it?

You need to have Vray and Brazil plugins installed in 3ds max in order to see these materials. Also Vray or Brazil should be set in the 3ds max Rendering settings as the active rendering engine.