[Mailman-Users] Users complain, they don't receive mails from the list

[Mark Sapiro]

On 01/25/2016 01:59 PM, Sascha Rissel wrote:
> 
> I have some user on my lists, who complain they don't receive the list
> mails anymore, since a few days.
> 
> Am am running Mailman 2.1.15 on Debian.
> The error log is empty, the archive seems to correctly contain all recent
> mails.
> The people saying, they don't receive the mails are on GMail and German
> Web.de hosts and they don't have bounces logged by Mailman.


If there is nothing in Mailman's error log or bounce log, it is almost
certain the mail is being delivered by Mailman to the outgoing MTA and
the outgoing MTA is successfully delivering the mail to the mail
exchange server for the recipient domain.

You can confirm this if you have access to the Mailman (and it's
outgoing MTA) server's mail.log.

If this is the case and the users have checked their gmail or web.de
spam or junk folders and the messages aren't there, the messages are
likely being silently discarded somewhere in the delivery chain after
leaving the outgoing MTA.

Solving this is difficult. Some steps are outlined in the FAQ article at
<http://wiki.list.org/x/4030690>.

I sometimes will copy the specific MTA log messages indicating
acceptance by the receiving MTA, e.g., messages like

Jan 24 19:09:41 sbh16 postfix/smtp[1053]: 1279111E1A8F:
to=<user at gmail.com>, relay=gmail-smtp-in.l.google.com[74.125.28.26]:25,
delay=5.8, delays=4.9/0.66/0.09/0.13, dsn=2.0.0, status=sent (250 2.0.0
OK 1453691381 tt2si3153213pac.167 - gsmtp)

and tell the user to ask gmail what happened to that message. In that
message, (250 2.0.0 OK 1453691381 tt2si3153213pac.167 - gsmtp) is the
acceptance from gmail-smtp-in.l.google.com indicating the message was
accepted at unix time stamp 1453691381 with the accepting server's ID
tt2si3153213pac.167. I suspect gmail actually ignores such requests from
their users or provides only a generic response. People who actually pay
for their email service may have a bit more leverage.

Anyway, apart from the things in the FAQ article, there's not a whole
lot you can do. If you can possibly identify something about the missing
mail that triggers it, e.g., only mail From: a certain user or domain,
or something in a specific thread (copied in everyone's reply), you can
try to avoid that, but if it's all list mail To: particular domains
(gmail), I think it's more likely to be a block on mail from your
server's IP, but in the US at least, gmail ordinarily bounces such mail
with a fairly specific reason.

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