Open Source IMAP Software

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.

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.

eMail traffic is on the rise. With over 100 man-years of development time behind it and a clean, intuitive interface that makes handling messages a breeze, Hermes Messenger (formerly known as QUALCOMM Eudora) is more than a way to send and receive mail: it's a powerful management tool with features to increase your productivity and enhance your communications. It is the best eMail program for people who get lots of it. If you're not yet one of them, you soon will be. Take control of your eMail before it takes control of you! Hermes provides industrial-strength communication, free of ads and free of cost.

hMailServer is a SMTP/POP3/IMAP server for Windows. Data is stored in MySQL/MSSQL database and is easily accessed using the COM library. Project info, trackers and downloads has moved to www.hmailserver.com.

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

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.

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

AtMail is an open source webmail client written in PHP. We aim to provide a elegant Ajax webmail client for existing IMAP mailservers, with less bloat and a focus on an intuitive, simple user interface.

OBM is a groupware, email, LDAP, Windows PDC, CRM, and project application mainly used as an Exchange or Notes/Domino replacement with groupware connectors for Outlook, Thunderbird/Lightning, and PDAs. It is highly scalable up to many thousands of users

An IMAP E-mail client for X-Windows written with GTK. Supports IMAP with and without SSL.

Quinsonnas Mail, a PHP4+/PEAR Web email client, retrieves mail from POP, IMAP, and NNTP server inboxes into a MySQL database. Mail is sent via SMTP, Sendmail, or PHP. MIME emails are supported as well. Contacts and lists are stored for composing email.