[Mailman-Users] unique Message-IDs

Mark Sapiro mark at msapiro.net
Thu Aug 25 11:48:21 EDT 2016

On 08/24/2016 11:20 AM, Beu, Ed (DOA) wrote:
> We've run into a situation whereas our email archiving system is puking on mail sent from large Mailman lists due to the Message-IDs all being the same on each individual message.
> I found the following article and tried it, without any success.
> https://mail.python.org/pipermail/mailman-users/2011-November/072525.html

Did you try just deleting the Message-ID or replacing it with a Mailman
Generated one?

If you are not VERPing or personalizing deliveries, replacing the
Message-ID will not be completely effective because the message with the
replaced Message-ID will still be sent to chunks with multiple
recipients. Whether deleting the Message-ID will be effective or not
will depend on when in its processing the MTA adds its own Message-ID.

> Any other suggestions?

Enable verp by putting


in mm_cfg.py and then replace the Message-ID with a Mailman generated
one per
or maybe just fix your archiving system.

Note that replacing the Message-ID in this way is a violation of mail
RFCs and I don't recommend it.

What happens if a local user sends a message with multiple To:, Cc:
and/or Bcc: recipients. Doesn't that confuse your archiving system too?
What do you do about that?

Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan

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