Please excuse me if this question has been asked.

 

I have a subscriber who on rare occasion has his posts rejected by LISTSERV ("Your message  is being returned to  you unprocessed because it appears to have already  been  distributed ...etc. etc.).  The posts rejected are always replies to another post, but they are NOT identical to a post in the archives, and his comments are added anyway which I would think would make the post unique.  I have looked everywhere I can find and have not been able to figure out what is causing the problem, but it almost appears as if the post is coming through and THEN it is being rejected as a duplicate.

 

This happens sporadically and I have not been able to come up with a pattern or anything.

 

Any help would be MOST appreciated.