Thanks for the quick response, and staying after office hours to reply.

The other modules included in the run are:
A/P 6.1A
A/R 6.1A
CONTACT MASTER 6.1D
COUNTER SALES 6.1C
G/L 7.0A
I/C 6.1B
QUICK HISTORY 6.5A

There is no open IR batch.
There is no indication in the verbose log that gives a clue as to which file the errors are in.
After running for several weeks with 4 errors, last night it found two more, so now we have 6.