Error when trying to Rename RefDes

Hi, I am using OrCAD PCB Designer V17.2.018.  When I try to Manufacture > Auto Rename RefDes > Rename..., using Default Grid, Rename all components checked I get:

Auto rename of reference designators in progress...
No components found on subclass TOP and BOTTOM.
E- (SPMHA1-390): Cannot open the log file.

I've done this before and had no problem; I've looked at everything I could find with no luck.

Anybody have any idea what is going on?

Thanks & regards,

John Madsen