Proxmox Mail Gateway - Protect mail server against spam, viruses and malware with Proxmox Mail Gateway security for businesses, government, education and non-profit organizations.
Barracuda Email Security Service - Secure Email Gateway
SpamAssassin - Use this program to "Unspam" your mailbox(es).
Cryptshare - Cryptshare is an online security company that gives its facility in securing your emails, uploading large files on cloud platforms to provide you with its compliance.
Rspamd - Rspamd is an advanced spam filtering system that allows evaluation of messages by a number of rules...
Scrollout F1 - Scrollout is a free and easy to use anti-spam email gateway designed for Linux & Windows administrators without advanced email security experience.