Open Source Email Software

SquirrelMail is a PHP-based Web email client. It includes built-in pure PHP support for IMAP and SMTP, and renders all pages in pure HTML 4.0 for maximum compatibility across browsers. It has strong MIME support and a flexible plugin system.

NOCC is a simple and fast Webmail client which can handle POP3 and IMAP mailboxes and sends email via SMTP. It is written with PHP, has low requirements (no database, frames). Features multi-language support, MIME attachments, displays HTML messages. The installation guide comes with the source code: https://sourceforge.net/p/nocc/code/HEAD/tree/trunk/webmail/docs/INSTALL If you encounter problems or bugs you can always try the current HEAD version: https://sourceforge.net/p/nocc/code/HEAD/tarball?path= Questions, bug reports or support requests are very welcome: https://sourceforge.net/p/nocc/_list/tickets Alternative source code repository: https://github.com/oheil/NOCC

QmailAdmin is a web interface for managing email addresses in virtual domains created by Vpopmail.

Kalkun is an open source web-based SMS (Short Message Service) manager. It uses Gammu SMSD (part of gammu family) as SMS gateway engine to deliver and retrieve messages from your phone/modem. Documentation is on the wiki: https://github.com/kalkun-sms/Kalkun/wiki Development and source code can be found on github: https://github.com/kalkun-sms/Kalkun/

Mail Notifier is free, modern email notifier with the latest user interface trends for Windows 10/11. It supports multiple accounts and IMAP/POP3 protocols. Enjoy customizable notifications, message previews, and more, all in 18 languages! For more details, please refer to the readme.txt file (Files tab, description below). Note: Gmail support is currently unavailable due to verification requirements by Google.

Thunderbird-Tray is a system tray launcher tool for Mozilla Thunderbird, the popular e-mail client. You can use TB-Tray to hide Thunderbird to the tray while you don't need it. When you click the tray icon, TB-Tray will restore Thunderbird.

Modest system requirements, decent performance, simple installation and upgrade, no database required - all these make RainLoop Webmail a perfect choice for your email solution.

Claws Mail is a GTK+ based, lightweight, and fast e-mail client and newsreader. Supports POP3, APOP, IMAP, SMTP, SMTP AUTH, NNTP, LDAP, multiple accounts, spell-checking, addressbook, SSL, GPG, filtering, i18n, & more. It is further extended by plugins.

The Mailredirect extension for Mozilla Thunderbird and Mozilla SeaMonkey adds the ability to redirect one or more email messages to one or more recipients. The feature of email redirecting is also known as remailing or resending. The extension is an answer for https://bugzil.la/12916

This program is an email antivirus/antispam gateway. It is an interface to the postfix or sendmail (or any other smtpd), which runs antivirus and/or spamchecker. Its modular architecture can use any combination of antivirus/spamchecker according to co

Claros InTouch is a webmail, instant messenger, addressbook, calendar and notes application. Written with usability and enterprise readiness in mind, Claros inTouch aims to fulfill the need for a stable, full featured Ajax messaging application

SMTP server, POP3 server, LDAP server, IMAP4 server, WWW administrator's interface

FUDforum is a super fast and scalable discussion forum. It is highly customizable and supports unlimited members, forums, posts, topics, polls & attachments. It can import XML Feeds and sync with USENET groups and Mailing Lists (bi-directional).

ItsEaling (Ealing Studios London UK) is a web based application which enables new p2p users to locate movies and new friends via the Internet. Expert p2p users can accumulate and trade p2p and other movie information for fun, recognition and cash.

Roundcube Webmail is a browser-based, multilingual IMAP client with an application-like user interface. Roundcube provides the full functionality you'd expect from an email client, including MIME support, address book, folder manipulation, message searching, and spell check. Roundcube is written in PHP and JavaScript.

Ontea - Pattern based Semantic Annotation Platform. Ontea search or create semantic meta data from text or documents using pattern based approaches. Implementation currently includes regular expressions (regex) patterns

KCheckGMail is a simple KDE systray application that notifies when new email is received in a Gmail/Google Mail/Google Hosted Domains account.

NETOFFICE EIS: CRM/SRM Corporate AddressBook ; iCAL Corporate Calendar + Agenda ; eMSG MailBox Email + Fax Messagery ; DMS FileManager + Document Management ; EXTM ModExpress (modules / extra apps: financial, sales) ; CPanel administration ; Intercha