Hola tengo el mismo problema y ya probe cambiando la resolucion, pasando a la placa de video de la placa madre en vez de la gtz 960 evga, reinstale el el vray nuevamente borrando el instalado, no se que mas hacer, alguien pudo resolverlo?
Has anyone tried installing Vray by right clicking and choosing run as administrator?
well, i follow this guy solution
wonder if it would work for you
Hi there. This one acctually helped. I used it one time. Obviously solves the problem in a wrong way… So it was banned. 
Could you share it again? i am facing the same issue