Cpanel’s Mailman is an open-source mailing list application. The problem is that there is no easy way to export subscribers from a list. Yet, here’s the solution.
Step 1: Login into account via SSH ( as root ).
Step 2: Find mailman directory. ( Default Location : /usr/local/cpanel/3rdparty/mailman/bin )
$ cd /usr/local/cpanel/3rdparty/mailman/bin
Step 3: Execute the following command to export subscribers to a text file:
$ ./list_members yourlistname > ./export_mail_list.txt
Example Mailman List Name : maillist_plugged.in ( If the subscriber list is firstname.lastname@example.org, the listname would be maillist_plugged.in )
This command will export my email subscribers into a file ( export_mail_list.txt ).