I installed a webmin module for mailman, virtualmin-mailman.wbm.gz. When I try to enable it I get “Failed to save enabled features : The plugin Mailman cannot be used : The mailman program /usr/lib/mailman/mail/mailman was not found on your system.”"
It sounds like you may still need the mailman package for your OS.
You have the Webmin module for it, which is good, but you’d also need the mailman package itself.
Thanks. It was installed however I saw this package: webmin-virtualmin-mailman in the repo, so I installed it and I was able to enable mailman. However I received an error that it couldn’t access a lock file. I tried to list the lock file but I found there was a link from /var/lib/mailman/locks -> /var/lock/mailman but /var/lock/mailman didn’t exist, so I created it and I was able to bring up the mailman admin page.
I ran into a number of other issues but eventually got it to work.