[Mailman-Users] Reducing false positives with spam markings with Gmail, etc.

[Stephen J. Turnbull]

Steven Clift writes:

 > Has this been a growing issue with Mailman served lists?

I wouldn't say it's growing.  For quite a while (a decade or so) we
have been getting the occasional request for help in getting mail
delivered to the major freemail services and portals, including Gmail,
Yahoo!, Hotmail, and AOL.  I haven't noticed them getting more
frequent over time, nor have I had problems delivering to them with my
own lists (but I have a really easy set of users to service, most are
admins or oldtimers themselves and tend to blame their freemail
provider, not my lists).

 > If it is not a growing problem with Mailman lists, then what are
 > you doing right!?

Hard to say.  For one thing, Mailman tries very hard to conform to the
relevant RFCs (specifically 5322, 2369, and 2919).

Second, most Mailman lists are set up by professionals, either people
who are quite familiar with mail service including the kinds of things
that keep you from getting labeled as spam, or hosting services.  Not
all of them are completely competent, but most do a pretty good job.
Most implement DKIM and/or SPF, for example.  So there may be a
growing problem, and we just don't hear about it -- the host managers
are dealing with it themselves.

Third, we do have a pretty good FAQ on how to communicate with the big
services to get on their good side.  It's tedious to follow their
rules, but it does work most of the time.

 > (One factor for us is that we do have a lot of users who post via
 > the web interface, which Gmail doesn't seem to like.)

That doesn't surprise me.  I assume that the from address is
"Web.User at home.org" as they are registered with your service.  If your
software is not emitting a correct Sender header, it will look like
the From address is spoofed.  Gmail won't like that.  Make sure that
in this case the Sender header is set appropriately.  (Mailman doesn't
have a web interface, so doesn't have experience with this itself.
The most common third-party interface is Gmane, which does get the
headers right.  Not everybody appreciates Gmane -- they have a habit
of mirroring lists whose owners don't want them mirrored -- but they
do conform to the mail standards.)

Hope this helps.

Steve