6.15. Mailman and Plesk
Some people use Mailman through Plesk, and they come to the Mailman mailing lists for help when they have trouble. There's usually little we can do to help with these specific problems, and you should contact your hosting provider or Plesk for assistance. You can also obtain assistance through the Plesk Forums at http://forum.odin.com (formerly http://forum.sw-soft.com/), using the search keyword "mailman". However, since none of the Mailman developers use Plesk, we are not likely to be able to help.
If there are specific problems with Mailman, they can contact us and we'll work with them as necessary to fix any bugs in Mailman that affect its use with Plesk.
This is similar to the problem with Mailman and CPanel.
If you're having problems with messages not getting out to your members, you may not have direct access to the level of information needed to debug the problem, but you should at least check out the standard debugging entry 4.78 Troubleshooting- No mail going out to lists members.
Some more notes regarding Mailman integration with Plesk, from a user/admin who has had personal experience:
Any version of Plesk higher than Plesk 7 comes with an older version of Mailman installed, and enables Plesk clients to add/remove mailman lists through their control panel. This is nifty, but does not come with the benefits of newer versions of Mailman, and because it seems so simple it trips alot of people up since it encourages them to set up Mailman lists when really they probably only need something simpler.
You can access the standard Mailman admin pages via a small "cogged wheel" icon to the far right of the respective list entry in the Plesk mailing lists listing page.
It is possible to trick Plesk into recognizing newer versions installed manually but it's not for the faint of heart.
Further information is available in this thread from the Plesk Forum: http://forum.odin.com/threads/fix-for-mailman-posts-being-rejected-due-to-yahoo-and-aol-dmarc-policy.302641/ from May 2014.
Converted from the Mailman FAQ Wizard
This is one of many Frequently Asked Questions.