postfix
Postfix Greylisting Policy Server
Postgrey is a Postfix policy server implementing greylisting developed by David Schweikert.
When a request for delivery of a mail is received by Postfix via SMTP, the triplet CLIENT_IP / SENDER / RECIPIENT is built. If it is the first time that this triplet is seen, or if the triplet was first seen, less than 5 minutes ago, then the mail gets rejected with a temporary error. Hopefully spammers or viruses will not try again later, as it is however required per RFC.
web based administration interface for Postfix mail servers.
Open Source email server
Regain your independence and protect your privacy by installing your own email server. It takes less than 10 minutes!
Modoboa is a mail hosting and management platform including a modern and simplified Web User Interface. It provides useful components such as an administration panel and webmail.
Virtual Mailbox Administration.
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Production-ready fullstack but simple mail server (SMTP, IMAP, LDAP, Antispam, Antivirus, etc.) running inside a container. Only configuration files, no SQL database. Keep it simple and versioned. Easy to deploy and upgrade. Documentation via MkDocs.
Fast, free and open-source spam filtering system.
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