Thank you for your feedback.
Please do the following steps to test the solution:
1. Download this zip file:
https://goo.gl/b7KKFp
2. Unzip, and run the IC7-CC3-Rov-OFF-2.reg to turn off the ROV feature in Character Creator 3.
3. Restart Character Creator 3 and let us know does the error still occur?
Reallusion Yep! I've got this error, but only sometimes after I tried to render with Iray.