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

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    A low-code dashboard makes monitoring intuitive for any admin, while scripting and custom sensors give experts full control.

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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: 441 This Week
    Last Update:
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  • 2
    Untangle
    Untangle is a Linux-based network gateway with pluggable modules for network applications like spam blocking, web filtering, anti-virus, anti-spyware, intrusion prevention, bandwidth control, captive portal, VPN, firewall, and more. Visit http://untangle.com
    Downloads: 20 This Week
    Last Update:
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  • 3
    Rumble Mail Server
    Rumble is a mail server suite for SMTP (ESMTPSA), HTTP, POP3 and IMAP4v1 with an extensive C/C++ and Lua API for scripting. It comes with support for SSL/TLS, SQLite and MySQL and has a web-based administration and webmail feature. Additional included modules feature greylisting, DNS blacklisting, SpamAssassin support and dynamic performance scaling as well as a multithreaded structure that allows for clustering of multiple servers for one or all domains, and with the ease of the Lua API, you can create your own new server mailing lists, CRM software, e-marketing and other extensions within minutes.
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    Downloads: 46 This Week
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  • 4
    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: 4 This Week
    Last Update:
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  • 5
    This is a command line date/time manipulation and formatting program, very useful in scripts. You can easily add or subtract days, hours and/or minutes from a specified date. Supports all date(1) output formats plus more.
    Downloads: 19 This Week
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  • 6
    QmailAdmin is a web interface for managing email addresses in virtual domains created by Vpopmail.
    Downloads: 4 This Week
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  • 7
    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: 3 This Week
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  • 8
    Vpopmail is a set of programs for creating and managing multiple virtual domains on a qmail server, with full support for many POP/IMAP servers. A web interface to vpopmail called QmailAdmin is on SourceForge as well.
    Downloads: 6 This Week
    Last Update:
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  • 9
    MailCleaner

    MailCleaner

    Anti Spam SMTP Gateway

    MailCleaner Open Source Edition is now discontinued but will continue under the spamtagger project https://github.com/SpamTagger [antispam] MailCleaner is an anti-spam / anti-virus filter SMTP gateway with user and admin web interfaces, quarantine, multi-domains, multi-templates, multi-languages. Using Bayes, RBLs, Spamassassin, MailScanner, ClamAV. Based on Debian. Enterprise ready. MailCleaner is an anti spam gateway installed between your mail infrastructure and the Internet. It includes a complete GNU/Linux OS and a graphical web interface for user and administrative access. It comes in the form of virtual machine templates.. - fully compatible with any SMTP mail server (Exchange, Zimbra, O365,...)
    Downloads: 2 This Week
    Last Update:
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  • 10
    Small HTTP server

    Small HTTP server

    Universal server

    It is not only a web server, it is also Mail server, DNS server, FTP server, TFTP server, Proxy server, VPN server and client... All in one! This program will help you to open all the possibilities Internet can offer for your company - public site, provide Internet access and personal mailboxes for each employee! HTTP server. Server Side Includes. Regular expression in SSI. CGI interface for scripts (Executable files; Perl,PHP, or another external interpreters) ISAPI interface. Virtual hosts and directories Mail POP3 server. SMTP server. FTP server HTTP proxy server DNS server DHCP server HTTP TLS VPN server
    Downloads: 9 This Week
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  • 11
    Faces - a Gtk+ program for monitoring a list (typically mail incoming messages) visually. It supports IMAP and POP mailboxes. There is a huge collection of picons (personal icons) that can be used in conjunction with the faces program.
    Downloads: 8 This Week
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  • 12
    Liberté Linux

    Liberté Linux

    Liberté Linux: Mission-critical stealth communication

    Liberté Linux is a secure, lightweight, and easy to use Gentoo-based Linux distribution intended as a communication aid in hostile environments. Liberté installs on a USB key, and boots on any computer or laptop.
    Downloads: 1 This Week
    Last Update:
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  • 13
    CRM114 is a Controllable Regex Mutilator and filter. It provides arbitrary stream filtering for antispam, adkiller proxies, syslog monitoring, etc. CRM114 has a structured, easily understood way to express regex-based filters, and a learn-by-example mod
    Downloads: 2 This Week
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  • 14
    DEPRECATED - This is now hosted at https://github.com/Yeraze/ytnef ytnef is a program to work with procmail to decode TNEF streams (winmail.dat attachments) like those created with Outlook. Unlike other similar programs, it can also create vCalendar/vCard entries from meeting requests, address cards, and task entries.
    Downloads: 2 This Week
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  • 15
    AMaViS is a script that interfaces a mail transport agent (MTA) with virus scanners.
    Downloads: 1 This Week
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  • 16
    Web-interface management for virtual domains, email-addresses and aliases for the courier mail server. Depends on MySQL and PhP
    Downloads: 1 This Week
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  • 17
    A small, fast, secure, anti-spam SMTP mail server (MTA). Delivery to mbox files and Maildirs supported. qwik-smtpd supports RBL, relay checking, raw/custom message handlers, and more. Custom authentication via checkpassword and a qmail-compatible configu
    Downloads: 1 This Week
    Last Update:
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  • 18
    Smtp Relay Checker is a network open mail relay checker. It is muti-threaded so it can be used to scan vast networks quickly, it is fully configurable so it can be adjusted to suit any need, and the scan results can be displayed in HTML. It is intended f
    Downloads: 1 This Week
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  • 19
    mairix is a tool for indexing and searching email messages stored in Maildir, MH, or mbox folders.
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    Downloads: 1 This Week
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  • 20
    Surblhost is a small program to look up hostnames in the Spam URI Realtime Blocklists (SURBL). Many spam filters and related programs use SURBL to determine if given hosts have been used as links in spam email.
    Downloads: 1 This Week
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  • 21
    APOP + LDAP authentication patch for QMail (auth_pop) 1. POP & APOP authentication 2. Passwords in LDAP are stored encrypted
    Downloads: 0 This Week
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  • 22
    Amber - a "grey list" for Qmail. Amber sits in the tcpserver chain, not accepting or rejecting mail but deferring connections from new IP addresses for some time (default five minutes) before it starts accepting mail from them.
    Downloads: 0 This Week
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  • 23
    This is an OS kernel for arm920t platform.
    Downloads: 0 This Week
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  • 24
    The program implements the CIDR merging with whitelisting (network exclusion). Output will be summarized to be as small as possible. The program has been widely used for blacklist merge and optimization.
    Downloads: 0 This Week
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  • 25
    CVTSA is a suite of tools for GNU/Linux that allows users to administrate computers via web or email wherever they are, using browsers or email clients [via computers or mobiles] and without running daemons[opening ports] on their own computer.
    Downloads: 0 This Week
    Last Update:
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