On 8/20/26 09:19, Christian H. Kuhn via Mailman-users wrote:
Hi all,
after upgrade from Ubuntu 25.10 (python3.13) to 26.04(python3.14) and
First and most importantly, Current Mailman does not support Python 3.14 because it depends on aiosmtpd and the current latest aiosmtpd 1.4.6 does not support Python 3.14. The GitHub branch at <https://github.com/aio-libs/aiosmtpd> does support Python 3.14, but it hasn't been released yet.
root@bywater ~ # python3 -m venv /opt/mailman/venv/
I don't understand. Are you creating a new venv? If so, you need to install Mailman in the new venv following <https://docs.mailman3.org/en/latest/install/virtualenv.html>.
If you do that, before installing Mailman in the venv, install aiosmtpd from github with
pip install git+https://github.com/aio-libs/aiosmtpd.git
You should probably also install Mailman core from gitlab with
pip install git+https://gitlab.com/mailman/mailman.git
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*
No module named 'mailman_web' is referring to /opt/mailman/venv/lib/python3.14/site-packages/mailman_web. Your installation is probably in /opt/mailman/venv/lib/python3.13/site-packages/
I don't understand what you have started with and what you have done. If you had a working Mailman in a venv with Python 3.13, I think the best approach would have been to install Python 3.13 along side Python 3.14, and you may still be able to do that.
If you want to proceed with Python 3.14, I think you need to create a new venv with Python 3.14 and first install aiosmtp from GitHub as above and then maybe mailman from GitLab as above
-- Mark Sapiro <mark@msapiro.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan