Re: [Exim] Multiple deliveries

| Hi all, I am getting the occasional reports from users about multiple
| deliveries. We are exim 4.24.
|
| It only happens rarely and then only to off campus addresses. Is it
| possible there is some timing issue, where exim sends the message and
| does not get an ack in time so sends it again. I am afraid I don't know
| what MTA is at the other end. If any of you have seen this before or
| have any ideas I would be grateful.

One possible cause of multiple deliveries is if the receiving server takes
too long to return the final 2xx response after the sending client has
sent the payload and terminating `.'. The sending MTA may time out and
retransmit the message later - hence duplicates occur.

See RFC 1047 for a discussion of this.

However, I assume this is mail your site sends _out_ that's affected ? -
in other words, there is no single slow receiving MTA that the finger
could be pointed at ?

Perhaps try to get hold of Received headers of some samples, and see if
you can tie these up with logs.

--
Chris Edwards, Glasgow University Computing Service