NeoCertified Secure Email - NeoCertified is a solution that provides secure email encryption for businesses and organizations across all industries, including healthcare, finance, legal, non-profit and education.
MailStore - MailStore Home - A 100% free single-private-user desktop solution
Proofpoint Email Encryption - As email is the preferred medium for business communications, preventing confidential information from being leaked in outbound email messages must be a top priority in order to lower the risk of a data breach.
MailSteward - MailSteward : The Ultimate E-mail Manager for Mac OS X
SendSafely - SendSafely operates a zero knowledge, end-to-end encrypted file exchange platform
Mail Backup X - Your one stop mail backup and archiving tool for Mac.