- Mailman-users - lists.mailman3.org

How to Choose the Best SMTP Relay Service Provider for Mailman?
by brucewilson3011＠gmail.com Sept. 2, 2026

Sept. 2, 2026

Reliable mailing-list delivery depends on much more than simply connecting Mailman to an SMTP server. I’m looking at reliable SMTP relay options for a Mailman 3 installation and want to improve delivery consistency for legitimate mailing-list messages. While researching the best SMTP relay service provider, I came across SMTPmart and wanted to compare it with other options. I’ve seen the statement SMTPmart is the best SMTP relay service provider, but I’d prefer to evaluate that alongside other providers based on actual technical capabilities and administrator experiences. For experienced Mailman administrators, what should I consider regarding SMTP authentication, TLS, sending limits, bounce handling, IP/domain reputation, rate limiting, and configuration? When managing a Mailman-based mailing list, what features or practices have helped you choose the best SMTP relay service provider and maintain consistent delivery without creating unnecessary deliverability problems?

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How to upgrade venv to python3.14?
by Christian H. Kuhn Aug. 20, 2026

Aug. 20, 2026

Hi all, after upgrade from Ubuntu 25.10 (python3.13) to 26.04(python3.14) and root@bywater ~ # python3 -m venv /opt/mailman/venv/ minutely: Traceback (most recent call last): File "/opt/mailman/venv/bin/mailman-web", line 3, in <module> from mailman_web.manage import main ModuleNotFoundError: No module named 'mailman_web' root@bywater /opt/mailman/venv/bin # ll mailm* -rwxr-xr-x 1 mailman www-data 204 Nov 5 2025 mailman* -rwxr-xr-x 1 mailman www-data 203 Nov 5 2025 mailman-web* root@bywater ~ # lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 26.04 LTS Release: 26.04 Codename: resolute root@bywater ~ # dpkg -l python3 ┌── Desired=Unknown/Install/Remove/Purge/Hold │┌─ Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend ││┌ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) │││ Name Version Architecture Description ├┼┼─══════════════─═══════════════─════════════─═══════════════════════════════════════════════════════════════════════> ii python3 3.14.3-0ubuntu2 amd64 interactive high-level object-oriented language (default python3 versio> root@bywater /opt/mailman/venv/lib/python3.14/site-packages # ll total 16 drwxr-x--- 4 root root 4096 Aug 13 15:09 ./ drwxr-x--- 3 root root 4096 Aug 13 15:09 ../ drwxr-x--- 5 root root 4096 Aug 13 15:09 pip/ drwxr-x--- 3 root root 4096 Aug 13 15:09 pip-25.1.1.dist-info/ In an older thread (Deb11 -> Deb12), i found: (venv) mailman@bywater:~$ pip install --force-reinstall mailman Traceback (most recent call last): File "/opt/mailman/venv/bin/pip", line 5, in <module> from pip._internal.cli.main import main ModuleNotFoundError: No module named 'pip' I'm a bit stuck here. I usually do not work with python, so i do not know how to proceed. Any hints? TIA QNo

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hyperkitty not archiving new mail
by Jaldhar H. Vyas Aug. 18, 2026

Aug. 18, 2026

Hello all, Mailman 3.3.10 on Debian 13. I recently upgraded from a well-running installation of Mailman2. Importing the existing mailing lists went well but I'm having problems with hyperkitty. First it was complaining that I didn't have a valid SSL certificate for localhost. I rectified that but in the mean time I ended up with some .pck files in /var/lib/mailman3/archives/hyperkitty/spool . Inspecting these with mailman-wrapper qfile reveals that they are messages which have been sent since the import. How do I reindex just those messages? I tried update_index and rebuild_index but apart from taking forever, they don't seem to help.

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urls.py location on venv install
by Torsten Aug. 12, 2026

Aug. 12, 2026

Hey all together, I have just nearly finished the migration of Mailman 3 from Debian packages to venv and mailman (master and runner) is up and running and uwsgi is also up and running. Just when I go to the web page https://<mydomain.tld>/mailman3 I get a server error and looking at the mailman web log I see that the ROOT_URLCONF seems to be missing. Following this thread: https://lists.mailman3.org/archives/list/mailman-users@mailman3.org/thread/… I added urls.py to /etc/mailman3 together with the other configuration files (settings.py, mailman.cfg and uwsgi.ini) and have added ROOT_URLCONF = 'urls' to /etc/settings.py but after restarting mailman (core) and mailman (web) the error is still there. What am I missing? TIA Torsten

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List Message Acceptance and Spam Filtering
by Washington Odhiambo Aug. 12, 2026

Aug. 12, 2026

Hello Admins, I am running MM3 3.3.11b3. The issue at hand also applies to 3.3.10. In my list setting, I have set "Default action to take when a non-member posts to the list" = Discard (no notification). In /etc/mailman3/mailman.cfg I have: [antispam] header_checks: X-Spam-Score: ^[4-9]\. Authentication-Results: dkim=neutral jump_chain: hold I am running rspamd on the host for Spam filtering. Now, I have a number of spam being sent to the list by non-members. The antispam rule in mailman.cfg matches and holds the email for moderation. I am failing to wrap my head around this behaviour. I was expecting that: 1. Any posts from non-members would be discarded 2. Mail classified as spam (from members) would be held for inspection by the list administrator. Can someone please help me untangle my thinking? -- Best regards, Odhiambo WASHINGTON, Nairobi,KE +254 7 3200 0004/+254 7 2274 3223 In an Internet failure case, the #1 suspect is a constant: DNS. "Oh, the cruft.", egrep -v '^$|^.*#' ¯\_(ツ)_/¯ :-) [How to ask smart questions: http://www.catb.org/~esr/faqs/smart-questions.html]

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Authentication of posts to a Mailman installation
by Steve Brown Aug. 12, 2026

Aug. 12, 2026

I have a suspect post that appears to be from a member but has a link to a potential scam site. I am not knowledgeable about spoofed addresses in the header; can a hacker simply put someone else's address somewhere in the header and have the message accepted if that address appears in the list of members? Steve Brown, administrator of a small list.

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Re: Thank you for the tips a year ago! Please help me gather other use-cases
by Archie Singh Aug. 7, 2026

Aug. 7, 2026

Hello, I am glad you asked these questions, as this can help anyone who will later wish to use the dynamic sublists feature for team collaboration when it is merged into Mailman 3. What does your suggested implementation look like? Would it be something > like main+sub-topic(a)example.com which would create a sub list called > “sub-topic” with inherited permissions from “main”? > Your guess is actually very close because a user will send a mail to a special alias, in your case main-new(a)example.com (with the -new command as a suffix to the parent list main(a)example.com) Then Mailman takes the message-ID, generates a database serial number, and using Base32 encoding generates a unique address for the child list (e.g., main-ab(a)example.com) And indeed because the child list is linked in the database via the parent_id, it inherits its settings from the parent list itself. What would that bring on top of including [sub-topic] in the subject or > body? It reduces inbox flooding :) When you use a subject tag on a mailing list it still follows the broadcast model; if a specific thread for troubleshooting or a specific project gets more replies, every single person on the main list will receive that many emails regardless of whether it was relevant to them or not. And thus, dynamic sublists is an opt-in thread model; the -new email is broadcast both to the main list (main(a)example.com) and the newly made child list ( main-ab(a)example.com) Mailman will send a separate announcement to the main list containing the -join and -leave addresses for the new child list. Also, the creator is automatically subscribed to the new child list and anyone else who is interested can opt-in. All the incoming replies from then on are routed to the child list. > I’m glad our little exchange on the MM3 list was helpful. A great example > of the power of searchable archives of such exchanges. Indeed :D Thanks again! Regards Archie On Fri, Aug 7, 2026 at 4:55 PM Rodrigo Camacho <rodrigo(a)vitz.fr> wrote: > > > > On 7 Aug 2026, at 13:09, Archie Singh <archie.singh2610(a)gmail.com> > wrote: > > > > I am Archie, a Google Summer of Code contributor for GNU Mailman and I > am working on implementing Dynamic Sublists, a type of conversation/thread > model into MM3. > > This sounds like a way to group a set of threads together through a > dynamically created list. > Today a similar result can be obtained (and often is) by adding something > like [UNIQUE ID OF TOPIC] to the subject or even the body of a set of > threads sent to one list. > > What does your suggested implementation look like? Would it be something > like main+sub-topic(a)example.com which would create a sub list called > “sub-topic” with inherited permissions from “main”? > What would that bring on top of including [sub-topic] in the subject or > body? > > > I wanted to let you know that your entire discussion thread was > something I wrote a blog about to explain (dated: 5th May 2026, > https://archiegnumailman.hashnode.dev/a-foundational-approach-to-replacing-…) > one of the use-cases of dynamic sublists and in fact if this feature was > present earlier in Mailman 3 you would have been able to utilize it for > your work :D > > I’m glad our little exchange on the MM3 list was helpful. A great example > of the power of searchable archives of such exchanges.

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New attack in progress
by Paul Tomblin Aug. 5, 2026

Aug. 5, 2026

Judging by the bounce messages I’m seeing, somebody or somebodies are trying to sign up for accounts on my Mailman instance using fake email addresses. Can’t imagine what the end game is, other than annoying people with “please confirm your email address” emails when they use a real address. -- Paul Tomblin

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Mass change Digest delivery mode
by iMark Aug. 5, 2026

Aug. 5, 2026

Hi All, Using the Mailman shell, can the delivery mode of Digests be changed to 'Plain text' for all users on just one list ? If it is, could someone tell me how that's done. Thanks, iMark

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How can we solve ZoneInfoNotFoundError
by Markus Grandpré Aug. 5, 2026

Aug. 5, 2026

Dear list members A user of our Mailman system reports having trouble logging in to access a mailing list archive. In the error messages that the Mailman system sends via email, we find: ... Internal Server Error: /mailman3/accounts/login/ ZoneInfoNotFoundError at /accounts/login/ 'No time zone found with key US/Eastern' Request Method: POST Request URL: https://mailman.uni-konstanz.de/mailman3/accounts/login/ Django Version: 4.2.28 Python Executable: /usr/bin/uwsgi-core Python Version: 3.13.5 ... Exception Type: ZoneInfoNotFoundError at /accounts/login/ Exception Value: 'No time zone found with key US/Eastern' Raised during: allauth.account.views.LoginView Request information: USER: **** GET: No GET data POST: csrfmiddlewaretoken = 'E6IT1iObdZYMyGKUgAHSxJ6LCzSZPDOKZmgVCaN9Kaae3s5gJy75Dwh8ptWjzcdI' login = '****' password = '****' next = '/mailman3/hyperkitty/list/basex-talk(a)mailman.uni-konstanz.de/' FILES: No FILES data COOKIES: csrftoken = '********************' ... (full error stack is attached to this email) Is there a server-side solution available for our GNU Mailman system 3.3.10 (Tom Sawyer), which runs on Debian GNU/Linux 13 (trixie)? Best regards, Markus Grandpré -- Markus Grandpré (he/him) Universität Konstanz Kommunikations-, Informations- und Medienzentrum (KIM) Abteilung IT-Dienste Forschung, Lehre und Infrastruktur Sachgebiet Diensteadministration 78457 Konstanz Tel: +49 7531 88-4342D

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