Similar to programs like Mailman or Listserv this extension allows you to run a discussion mailing list.

That means that every email sent to a central email address is forwarded to the rest of the members of the list. When members reply to such emails Mailster again forwards them to the other list recipients.

Mailster allows your users to be part of a group and communicate by email without having to log into your Joomla site.

This is primarily made with discussion email lists (two way communication) in mind, although Mailster can also be used for newsletters.

Features
- For Group communication and newsletters
- Usable with any POP3/IMAP email account
- Recipients are managed by the admin in the backend
- Users can (un)subscribe with frontend plugin or module (optional)
- All Joomla users can be chosen as recipients, additional users can be stored
- Users can be organized in groups
- Single users or whole groups can be added as recipients of a mailing list
- Replies to mailing list posts can be forwarded to all recipients
- Mail archive for browsing the mails
- Full support of HTML emails and attachments
- Seamless installation: all plugins are included and are installed automatically
- English, German, French, Dutch, Italian, Danish, Japanese and Slovenian translation included
- many more features

Designed for all...
- users that are tired of group messaging systems that require another login
- users who want to communicate with their favourite mail client
- admins that are tired of updating personal details on different systems
- admins who want to be able to use users within Joomla as recipients of a mailing list

Changelog

Version 1.5.2 (20th August 2019)
- Cronjob optimization for the "all" execution mode. Avoids sending delays for installations with many lists.
- Enable to sleep only 0.1 or 0.5 seconds with the "wait between the sending of two mails" functionality to allow for more reasonable performance while adhering to limits
- Show charset conversion functionality missing in system diagnosis
- 5 bug fixes

Version 1.5.1 (27th December 2018)
- Subscriber Module only shows options for subscribe form when this type of module was chosen (and unsubscribe respectively)
- Database optimization to allow for quicker searches
- Remove unneeded settings
- 4 bug fixes

Version 1.5.0 (25th May 2018)
- Subscription log in which subcription/unsubscription actions are recorded for audit purposes (GDPR / DSGVO)
- Subscription log can be exported to CSV file
- Subscription Module and Plugin: new option to require a terms of service acceptance before subscription
- 10+ bug fixes

Version 1.4.1 (23th February 2018)
- Allow to block emails based on domain and/or host name and/or top-level-domain (examples: @mail.ru, sales@.in) in global filter settings
- Auto-correct some special cases where the text editor screw up the HTML-based unsubscribe URLs
- De-selecting "Allowed to send/post" restricted settings (e.g. admin) works
- Subscriber plugin shows unsubscribe forms correctly again
- Inline images send by iPhone/iPad Mail Clients show up correctly in Mailster's mails
- 5+ other bug fixes

Note that this version has limitations (e.g. max. 50 recipients per list) compared to our commercial products Mailster Essential, Business and Ultimate. Find a feature comparison overview here: http://www.brandt-oss.com/index.php/mailster/pricing