Proxmox Mail Gateway - Protect mail server against spam, viruses and malware with Proxmox Mail Gateway security for businesses, government, education and non-profit organizations.
SpamTitan - Comprehensive Email Protection. 99.99% Spam Detection. Blocks phishing, viruses, malware and other email threats.
SpamAssassin - Use this program to "Unspam" your mailbox(es).
Sanebox - SaneBox is a cloud-based service that allows users to filter and manage their emails.
Rspamd - Rspamd is an advanced spam filtering system that allows evaluation of messages by a number of rules...
MailCleaner - Cloud & on-premise anti spam software for businesses