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.

Elastix is a software-based PBX powered by 3CX and based on Debian. An open-standards solution, Elastix is an easy to install and manage UC system compatible with popular IP phones, gateways and SIP trunks. Elastix is complete with unified communications features such as integrated WebRTC video conferencing, chat, presence and softphones and smartphone clients for Windows, Mac, iOS and Android.

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/

Simple, web-based address & phone book, contact manager, organizer. Groups, addresses, e-Mails, phone numbers & birthdays. vCards, LDIF, Excel, iPhone, Gmail & Google-Maps supported. PHP / MySQL based.

Zentyal Server is an easy to use and affordable Linux server, specially designed to meet the needs of small and medium businesses Thanks to Zentyal's Samba integration, Zentyal provides native compatibility with Microsoft Active Directory, allowing you to join Microsoft clients to a domain and manage them easily. Zentyal Server incorporates all the network services required in a small and medium business environment: * Directory & Domain Server with native compatibility with Microsoft Active Directory * Mail Server with ActiveSync and webmail * Gateway with firewall and proxy * Infrastructure Server with DNS/DHCP server, Certification Authority and Virtual Private Networks For more information and download, please access the project's home page.

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.

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

Mailman is the GNU mailing list manager. It provides standard list management features, integrated with a web interface. Please note: the subversion repository has been retired. Please see http://wiki.list.org/x/DgAJ for details.

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

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).

Программа для рассылки почтовых сообщений через smtp. /Program for mass delivery of email through smtp. Can transfer a plain text to many e-mails with templates. Now https://github.com/zlv/SpamTeacher

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.

Gmail Herald is Qt based application that alerts when you have new Gmail messages and allows to mark them as read. It displays an icon in your system tray to let you know if you have unread emails, and shows you their subjects, senders and snippets, all without a web browser.

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.

Strike the 'T' key to sort messages by thread, strike the 'U' key to sort unthreaded again, just like the 'G' key switches to Grouped By Sort view.

GoldBug is a decentralized & secure communication suite that offers an integrated e-mail client, an instant messenger & a file transfer. Also included is an URL-RSS-DB & a p2p web search. Current vers. w/ McEliece Algorithm. GoldBug has been 2013 - 2023 ten years just another Graphical User Interface of the Spot-On Encryption Suite. Main GUI features: Minimal & colorful Interface with Tabs in the East. Microsoft & Qt MinGW deprecated Win32 & for Compiling: ● https://sourceforge.net/p/goldbug/wiki/compiling As Spot-On implemented the minimal GB-concept & Nuvola Icons, GoldBug has now been fully integrated into Spot-On Win64: Just choose Tabs at East & Mini-View in Options - w/ Nuvola Icons of course! Voilá! & Many Thanks, Pro-Files can be found archived at ● current source: https://github.com/textbrowser/spot-on ● EN Manual: https://www.amazon.com/dp/3749435065 ● DE: https://compendio.github.io/goldbug-manual-de/ ● Study: https://www.amazon.com/asin/dp/3750408971

P3Scan is a fully transparent scanning proxy-server for email clients. It provides scanning of incoming/outgoing email messages for Virus''s, Worms, Trojans, Spam, and harmfull attachments. It can also parse messages for web-bugs.

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

Googsystray is a system tray app for Google Voice, GMail, Google Calendar, Google Reader, and Google Docs. It notifies on new messages, alerts, etc., and provides basic services quickly.

The Address Book is a free, open source address management system, utilizing the combined power of PHP scripting and MySQL databases to provide a flexible, robust system allowing users to add a virtually unlimited number of addresses and other info.

Fix incorrect charset information in Content-Type MIME headers of e-mail messages.

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

SmartSieve is a web based graphical user interface for creating and managing sieve scripts for mail filtering and vacation messaging on a cyrus imap mail server. Written in PHP, SmartSieve is easy to configure and use.

Free and easy-to-use webmail script with AJAX interface. Supports POP3/IMAP accounts, SMTP, SSL. Users can check and send mail, use address book. Skins, non-English languages, UTF-8. MS SQL/MySQL/MS Access backends supported.

AfterLogic WebMail Lite PHP is a free AJAX webmail application. Users can receive, view, manage, compose, and send email through web interface (IMAP and SMTP supported). Source code included.