Author: Tom Kistner Date: To: Ian Freislich CC: exim-users Subject: Re: [exim] An interesting problem (apparent duplicate delivery)
Ian Freislich wrote:
> This phenomenon doesn't appear to be confined to one server or to
> a particular user and it happens to random messages (or at least I
> haven't found a pattern yet).
Do you use AV or spam scanning after DATA? If yes, the cause may be a
post-data timeout on the sending host. Exim may then send his 220 to a
dead channel and queue the message, while the sending host has timed out
the SMTP session and will retry sending the message later.
That would explain the randomness. It typically only happens when the
machine is well-loaded.
