SpamHero - SpamHero is a professional spam filtering accuracy while lowering the cost to domain and business owners.
MailStore - MailStore Home - A 100% free single-private-user desktop solution
SpamAssassin - Use this program to "Unspam" your mailbox(es).
Intradyn Email Archiver - Orca Email Archiver provides email archiving solution for local government and business.
SpamTitan - Comprehensive Email Protection. 99.99% Spam Detection. Blocks phishing, viruses, malware and other email threats.
Hornetsecurity Email Archiving - Hornetsecurity Email Archiving is one of the advanced software that offers long-term, unchangeable, and secure storage of important company information, data, and flies.