Hey I had the exact same problem.

what i found was that the "virtual visitor" had set it's eye height to more than 3 meters....

It is a bit weird because i could still see everything in the 3d view. but it wouldn't catch much during rendering.

anyhow i put it to 170 cm or so and it works again.

maybe checking the settings of the "virtual visitor" in the 3d menu will solve your problem...