Anti-Spam SMTP Proxy Server

Anti-Spam SMTP Proxy “Anti-Spam SMTP Proxy” is a spam filter that sits on port 25 (smtp), and optionally also 465 (smtps) and 587 (submission), in front of your regular SMTP server.

ASSP relays the SMTP dialog between an incoming client and your SMTP server, intercepting the dialog as needed. ASSP performs a number of configurable spam checks and on detectinga spam message provides an immediate 5xx SMTP error code back to the client.

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