Open Source BSD Post-Office Software

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.

Fetchmail is a mail retrieval daemon that can download messages from POP3, IMAP, ODMR and ETRN-based stores, with SSL/TLS security including certificate verification, and pass downloaded mail to a local SMTP or LMTP server, or a message delivery agent such as maildrop.

FreePOPs is a webmail to pop3 conversion daemon. It is extensible to support other webmail using the scripting language LUA. See the homepage for supported webmails.

Columba is an email client written in Java, featuring a user-friendly graphical interface with wizards and internalionalization support. Its a powerful mail management tool with features to enhance your productivity and communication.

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

ZMail allows you to send email from anyone, to anyone. You can use ZMail to send fake or anonymous emails. Have fun!

A command line utility for synchronizing remote IMAP mailboxes and local maildir-style mailboxes. This is useful for working in disconnected (off-line) mode, such as on a laptop, but also for mirroring mailboxes between servers.

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!

New Maintainer wanted! I'm looking for a new maintainer for this project because I'm not able to attend it anymore. If you want to help please write to kuddel-fl. KShowmail is a POP3 mail checker for the KDE with these features: show number, size and more information about mails on pop3 servers in a list view, show the mail headers or complete mails, delete unwanted mail from server by configurable filters.

Hastymail is a fast, secure, rfc-compliant, cross-platform IMAP/SMTP client application written in PHP providing a clean web interface for sending and reading E-mail. This version of Hastymail is no longer being developed. We are now working on a new version, Hastymail 3, AKA, "Cypht". http://cypht.org

Convert Webmail to POP3.Is also included a SMTP/POP3 tunneling system that allow send and receive email in a private network HTTP PROXY based. All connection are plugin based. Over 450 email server supported and tested, GMAIL POP3/SMTP over Proxy Network.

jwSMTP, Send email programmatically (C++ code/lib). Linux, BSD, Windows etc. Attachments, Multiple recipients, Cc/Bcc recipients supported. MX lookup or send to an SMTP server direct. LOGIN and PLAIN authentication now supported. Html or plain text forma

Set of pure useful Java utilities taking care of common tasks and avoiding re-write of code

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...

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.

hotwayd/hotsmtpd are POP3/SMTP-HTTPMail gateway daemons. The HTTPMail protocol is used by the mail servers Hotmail, Lycos, Spray and MSN. The hotway suite you can receive and send mail via these services using any POP3/SMTP compliant mail reader.

smm is a anti-spam, mail-shaper, delete-on-server software thought for users who have a slow dialup connection and are sick and tired of downloading 1MB a day of spam and Win32-worm-attached messages.

Heirloom mailx (formerly known as "nail") is intended provide the functionality of the POSIX mailx command with additional support for MIME messages, IMAP (including caching), POP3, SMTP, S/MIME, message threading/sorting, scoring, and filtering.

liberopops is useful for users of Libero provider who cannot read email due to its change of policy. It acts as a POP3 server which interfaces itself to the webmail service still available.

NMail provides an SMTP client & server along with an IMAP4 server; all are written in C#.

gavamail is a POP3/IMAP server implemented in JAVA for reading your gmail e-mail with your favorite mail client. Currently only POP3 is implemented but I hope to implement IMAP too. Libraries provided by the g4j and libgmail projects are used.

pop3spam is a POP3 client which connects to a POP3 server and deletes unsolicited mail in-place. It's possible to check for messages that exceed a certain limit and to scan header lines for special patterns (regular expressions).

BitMail is a Proof-of-Concept- / Design-Study for an Qt E-Mail Client. POP3 / IMAP / SMTP / P2P E-Mail-Client. ● Qt E-Mail Client. ● Build-in Encryption to secure E-Mails ● IMAP & POP3 ● Additionally a full decentral P2P Email-Option via the Echo Protocol ● Store Email for Offline-Friends in the P2P Network. ● Chat and Instant Messaging is build in. ● POPTASTIC function (Chat over Email) ● Calendar widget functionality. ● Open Source. BSD License. "Cassiopeia is the tortoise of Momo, which can communicate through writing on her shell and guides into the future." - Wikipedia. Source from: https://sf.net/projects/spot-on/files/ & https://github.com/textbrowser/spot-on

Cyrus IMAPd is a popular IMAP server that surfaces a rich interface for extending its functionality. The Cyrus IMAPd Utilities project brings together maintenance utilities, graphical front-ends, and API handlers (such as notification daemons).

IMAP-Agent is an automated IMAP mail folder management system implementing site wide and individual user specific rules for filtering mail between folders. Also, quotas can be maintained by age or max count of messages for any folder.