Open Source Linux Email Clients

Free Windows Mbox Viewer. Gain access to mbox archives or single eml messages. View attachments and export single mails in eml format. Access large mbox files such as Google Takeout or Mozilla Thunderbird Archives. Development of mbox viewer continues now at github: https://github.com/eneam/mboxviewer **NOTE**: Windows Defender may sometimes report incorrectly that mbox-viewer contains malware. Please report the case to the development. Development will ask Windows Security to update Windows Defender rules to resolve the issue. Last time the incorrect detection was corrected by Microsoft Security within few hours. User will need to run Windows Update to install the latest updated detection rules.

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.

Mailspring is a fast and lean mail client that’s a new version of Nylas Mail. It’s maintained by one of Nylas Mail’s original authors, with plenty of great features and enhancements such as a new C++ sync engine that allows it to use 50% less RAM. Heavy dependencies have also been removed and the package manager rewritten for even greater speed. Written in TypeScript with Electron and React, it is cross-platform (macOS, Windows and Linux) and designed to be easy to extend.

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

Tutanota is an open source email client focused on security and privacy. It is built with end-to-end encryption and 2FA, so you can be assured of utmost email security. Tutanota is always encrypted, so whether you’re using their secure webmail client, mobile apps or desktop clients, you can be sure to communicate securely.

Trojitá, a Qt IMAP e-mail client

SaltOS is a Business Management solution 100% Cloud Computing. It integrates features like CRM (Customer Relation Management) and ERP (Enterprise Resource Planning). Moreover is it licensed as 100% free software GPL-3.0.

All your E-mail, from all your accounts, in one place. Cypht is not your father's webmail. Unless you are one of my daughters, in which case it is your father's webmail. Cypht is like a news reader, but for E-mail. Cypht does not replace your existing accounts - it combines them into one. And it's also a news reader. The driving force behind Cypht development is to provide combined views for multiple accounts, but it's also a standard E-mail client that lets you browse and manage IMAP folders and send outbound messages with SMTP. Cypht is an application built entirely of plugins, or as we call them, module sets (which is obviously way cooler sounding than plugins), that are executed by the framework. Modules provide a flexible way to add new features or customize the program without hacking the code. Cypht is Open Source (LGPL V2), and written in PHP and JavaScript.

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

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.

Add support for making Gmail the default mail application for the GNOME desktop. "Gmail" will be a choice for Mail Reader in the Preferred Applications dialog. "Mailto" links, "Send Link", etc., will be handled by Gmail.

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

MultiMail is an offline mail packet reader for Unix and other systems. It currently supports the Blue Wave, QWK, OMEN, OPX and SOUP formats. It has a full screen, color user interface, built with the curses library.

OpenChange is a portable Open Source implementation of Microsoft Exchange server and Exchange protocols. It provides a complete solution to interoperate with Microsoft Outlook clients or Microsoft Exchange servers. OpenChange client-side library is used in existing messaging clients and is the solution in new projects to communicate natively with Microsoft Exchange and Exchange-compatible servers. OpenChange server is a transparent Microsoft Exchange server replacement using native Exchange protocols and does not require any plugin installation in Outlook.

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.

Note! Code and issues are maintained at https://github.com/sba1/simplemail. SimpleMail is a simple to use but powerful mail client. It supports the SMTP, POP3 and IMAP (in a simple form) protocols. Furthermore, among much other features, it is capable of showing HTML mails and can identify spam mails by using a Bayesian filter.

Notifier for multiple Gmail and Google Apps email accounts. Offers various notification options (unread mails in Inbox only, All Mails, or with specified labels) and alert methods (popup message, chime, blink keyboard LED). Uses IMAP over SSL.

exmh is a user interface to the MH (a.k.a. nmh) email system. It is extensible and its users have exploited this to integrate PGP, Glimpse, ispell, faces/picons, MIME, and much more.

JMail is a mail client written in Java. It handles attached files, HTML mails, filters and other stuff... It can be used with a LDAP directory.

libgmailer for PHP consists of 2 parts: {GMailer (libgmailer)} a PHP class/library for you to access GMail with PHP with ease. {gmail-lite} a plain HTML only interface of GMail, accessible by any browser on Earth.

RFC 2425 defines a MIME Content-Type for Directory Information. This library contains necessary methods to parse information blocks arranged in such a manner.

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.

Tiny application based on readpst and dbxconv that provides a convenient GUI to convert Outlook and Outlook Express files into open standards. The program converts Outlook Express 5/6 .DBX to .EML and Outlook 2003/2007/2010 .PST to MBOX. The program runs only on Linux machines and doesn't need any Microsoft software!

iMailist is a software allowing the sending of mails to format HTML to a whole mailing-list. The program is written in Objective-C/Cocoa and works on Mac OS 10.3

Koolwired.Imap is a fully managed .NET IMAP client library written in C#.