Browse free open source C Mail Transfer Agents and projects below. Use the toggles on the left to filter open source C Mail Transfer Agents by OS, license, language, programming language, and project status.

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  • 1
    The Courier mail transfer agent (MTA) is an integrated mail/groupware server based on open commodity protocols such as ESMTP, IMAP, POP3, LDAP, SSL, and HTTP. Courier provides ESMTP, IMAP, POP3, Webmail, calendaring, and mailing list services.
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    Downloads: 1,119 This Week
    Last Update:
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  • 2
    IndiMail
    Highly scalable/configurable Messaging Platform allowing users in a domain to be distributed on multiple hosts, has multiple queues. Provides virtual domains/users in MySQL. Modern MSP class qmail replacement with ESMTP, POP3/IMAP, QMTP, QMQP support
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    Downloads: 20 This Week
    Last Update:
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  • 3
    YPOPs! is an application which emulates a POP3/SMTP mail server and provides free POP3 and SMTP access to Yahoo! Mail. It does not depend on Yahoo's POP3/SMTP mail server. You can use a mail client of your choice!
    Downloads: 11 This Week
    Last Update:
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  • 4
    ESMTP MTA is a user configurable relay-only MTA with a sendmail-compatible syntax, based on libESMTP and supporting the AUTH (including the CRAM-MD5 and NTLM SASL mechanisms) and the StartTLS SMTP extensions.
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    Downloads: 36 This Week
    Last Update:
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  • 5
    A qmail patch which provides plug-in support for it`s SMTP daemon.
    Downloads: 17 This Week
    Last Update:
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  • 6
    machiNET Mailserver

    machiNET Mailserver

    Mail system postfix dovecot openldap contact syncronization

    Machinet mailserver is a setup for a (small) enterprise mail server using standard GPL components
    Downloads: 3 This Week
    Last Update:
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  • 7
    Tools for a mail delivery service, including LMTP and POP3 servers and also getpwnam() emulation. Mail is stored in Maildir++ format (qmail plus courier extensions as soft quota and subfolders). User defined filter and virtual domains are supported.
    Downloads: 4 This Week
    Last Update:
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  • 8
    SpamAssassin in exim at SMTP time & Greylisting, using the local_scan hook
    Downloads: 1 This Week
    Last Update:
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  • 9
    AISK is an acronym for Artificial Intelligence Spam Killer. It is a server side filter that acts as a kind of PROXY and uses SMTP to communicate with MTA. Main decision mechanism is based on artificial neural network capable of finding patterns, learning
    Downloads: 0 This Week
    Last Update:
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    For companies looking to automate their consolidation and financial statement function

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  • 10
    ASMMS -- Anonymous SMTP Mail Message Sender ... is an simple mta, written in C, for sending mails through mail servers, which have no authentication (AUTH). It should work on nearly all POSIX systems, tested only with SunOS, Linux and HPUX.
    Downloads: 0 This Week
    Last Update:
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  • 11
    SORBS - Spam and Open Relay Blocking System - NOT http://www.sorbs.net/ This project is to provide a SMTP proxy that automatically checks incoming SMTP connections for origination from a server with an unsecured SMTP server and/or Proxy server.
    Downloads: 0 This Week
    Last Update:
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  • 12
    This project aims to be a personal data storage and administration system. It will be an advanced system for information and electronic mail management. The server will be accessible to any IMAPv4 compatible mail client.
    Downloads: 0 This Week
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  • 13

    CRM114 MILTER

    CRM114 milter for sendmail

    This is a milter which scans emails with CRM114
    Downloads: 0 This Week
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  • 14
    Clam AntiVirus

    Clam AntiVirus

    The free cross-platform antivirus software tool-kit

    ALL DOWNLOADS HAVE MIGRATED TO HTTPS://WWW.CLAMAV.NET Clam AntiVirus is a GPL cross platform antivirus toolkit. The main purpose of this software is the integration with mail servers. It provides a flexible and scalable multi-threaded daemon, a command line scanner, and an up-to-date virus database. Github Repo is here: https://github.com/Cisco-Talos/clamav-devel
    Downloads: 0 This Week
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  • 15
    The complete mail system consist of mail client written in php and mail transfer agent written in c language.
    Downloads: 0 This Week
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  • 16
    The EZ-qmail distribution is an EZ method for hobbyists / small businesses to try the qmail system for mail delivery. It provides an EZ to install, modern (patched) and working (integrated) qmail system onto which additional functionalities can be added
    Downloads: 0 This Week
    Last Update:
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  • 17
    F1-Mailer : A simple Mailer in command line for windows users with MIME format. F1-Meiler allows people sending emails via SMTP relaying servers on the Web, with mail attachement. File attachment and email dating support. A tool to begin in Web/SMTP.
    Downloads: 0 This Week
    Last Update:
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  • 18
    FLex Smtp Server is a Fast, Lightweight EXtendable Smtp Server. While having basic protocol support, is aimed to manage heavy traffic also in a burst modality.
    Downloads: 0 This Week
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  • 19
    FMTA is a simple SMTP/POP3 server designed to run on Fox boards (Fox board is a small but powerful embedded computer running a complete GNU/Linux system).
    Downloads: 0 This Week
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  • 20
    Forpost is an embeddable, interpreted stack-based(Forth-like) language which has simple, compact and effective implementation in ANSI C. Main features: heterogeneous arrays, higher-order functions, program/data equivalence.
    Downloads: 0 This Week
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  • 21
    Fork of the OpenBSD spamd for the FreeBSD operating system. See http://www.openbsd.org/spamd/ for the original spamd documentation. Please, report there only FreeBSD related bugs. If you want join to the project - write mail to the samm user.
    Downloads: 0 This Week
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  • 22
    An advanced qmail distribution based on qmail-sql which has SMTP, SMTPS, POP3, POP3S, IMAP, IMAPS services, a content scanner, spoofing protections, SMTP AUTH support, SMTP-after-POP/IMAP, PHP5 API, SPF support and much more...
    Downloads: 0 This Week
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  • 23
    IDMS DBMA is an effort to develop a highly scalable (c10k complient) plugin based mail agent aimed at fighting spam & viruses. Hopefully replacing hard-to-maintain, complex, resource hungry configurations used by small to large users today.
    Downloads: 0 This Week
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  • 24
    IVS Milter is a plugin based content filtering milter. It currently supports... Virus (ClamAV) & Spam (SpamAssassin) scanning, Content-type, Attachment type & Attachment filename matching
    Downloads: 0 This Week
    Last Update:
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  • 25
    InfinyMail is an ODMR (RFC 2645) implementation, consisting of client and server. The client request its mail to the provider (ISP's MTA) via ODMR protocol.
    Downloads: 0 This Week
    Last Update:
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