How to Deal with Black Render?

James

Often times rendering process stops immediately after I hit render button and left with a black screen.
Usually it happened after 2 or 3x rendering.
The vieport can't show the image in iray too. Iray mode only show grayscale.

I've tried to search for soultion this forum, but I  can't find a definitive solution.

All I know this is the problem with the iray technology itself. Something about inability of the technology to empty its own vram.

Usually I just close DAZ and start again.

But it costs time.

Is there a faster way?