I also had this error on another object in the scene that was in a group but I remembered somewhere about groups sometimes causing this problem (I think I did anyway)…it resolved the issue for that particular object.
If I set refraction colour to black it doesn’t produce the error. If I turn off the direct light it stops the error, but I need the direct light.
Max 2012 - vray 2.xx (latest).
Hi Steve,
Stupid question - you are using vrayshadows on the direct light?
Yep, using vray area shadows..
ok. I went through a number of tests, tried rendering just the geometry causing the error (in isolation mode with lights still rendering) and it was fine. I noticed my render was still going slowly on sections of the image where phoenix was being used (even though there was no simulation on that frame) and so I deleted the phoenix sim and hey presto, all is fine.
Is there a reason Phoenix would be causing this problem…
I can think of several reasons 
Can you get us the scene?
Best regards,
Vlado
Do you require the texture maps as well…the phoenix sim is fairly large so you will have to do that…if thats ok 