Mailman is free software for managing electronic mail discussion and e-newsletter lists. Mailman is integrated with the web, making it easy for users to manage their accounts and for list owners to administer their lists. Mailman supports built-in archiving, automatic bounce processing, content filtering, digest delivery, spam filters, and more
If you are using Mailing list on a cPanel server and migrated it to another server or made changes in the server hostname, the link of the Mailman may not work. In this case, you will need to update the link from command line.
Example:
Old server Mailman link: http://host.example.com/mailman/admin/list_name
New server Mailman link: http://host2.example.com/mailman/admin/list_name
To the change the Mailman link:
1) Login to the server via SSH and go to
/usr/local/cpanel/3rdparty/mailman/bin
2) Execute command
./withlist -l -r fix_url list_name --urlhost=host2.example.com
where host2.example.com is the new hostname
Note: replace the hostname with your server hostname at --urlhost