ChoiceMail One is DigiPortals critically acclaimed anti -spam software. ChoiceMail blocks 100% of spam with absolute certainty. ChoiceMail allows you to choose which messages come to your inbox. Take control of your email again with ChoiceMail.
The Axigen Free Mail Server is a great alternative to open source: it is an all-in-one, turnkey messaging solution, with an amazing number of free users (100 basic email users, calendaring for 5 users included).
SpamButcher is an advanced anti-spam filter. Its spam blocker can stop 98% of spam. Every few minutes it checks for new messages in your inbox. If it finds any spam, it’s moved to a holding area for later examination.
AXIGEN Mail Server – a complete messaging solution backed up by first rate tech support; available for Windows Server 2003 / 2008; (E)SMTP / POP3 / IMAP4 / Webmail, centralized Web / CLI Admin, Groupware, Personal Organizer, FREE technical support.
AXIGEN Mail Server – a complete messaging solution for Linux, BSD, Solaris; offers (E)SMTP, POP3, IMAP4 and Webmail services, Personal Organizer, Groupware, enhanced security features, centralized Web / CLI Admin and FREE technical support.
Open source DKIM library and MTA filter implementation
Policy Daemon is an anti-spam plugin for Postfix.
Usermin For Webmail is a modified version of the Usermin package that is pre-configured for use as a Web-based email client.