Best Open Source Email Software 2026

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Browse free open source Email software and projects below. Use the toggles on the left to filter open source Email software by OS, license, language, programming language, and project status.

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1

Mail Alert Simple Mailer

Mail Alert Simple Mailer

Mail Alert Simple Mailer is a simple command-line utility designed for IT administrators for sending e-mail from Microsoft Windows OS. It can be executed from command line, Windows batch file or PowerShell scripts. My main reason for writing this software was to handle events generated by Dell OpenManage Server Administrator (OMSA), APC PowerChute and Windows Events to send hardware status and alerts like temperature alerts, UPS battery status, powerline status and RAID controller alerts from monitoring software. It can be used with any other software where you can configure external application to be executed when specific event occurs. Mail Alert Simple Mailer supports SSL and STARTTLS protocols, so it is compatible with many free e-mail providers like GMail, Hotmail, etc. Unlike other simple command line tools it supports ISO-8859-1, ISO-8859-2 and UTF-8 code pages for national characters. Mail Alert Simple Mailer encrypts SMTP password in configuration file.

5 Reviews

Downloads: 6 This Week

Last Update: 2018-07-03
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2

QmailAdmin

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

4 Reviews

Downloads: 4 This Week

Last Update: 2016-07-25
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3

P3Scan

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.

Downloads: 6 This Week

Last Update: 2013-04-17
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4

Thunderbird-Tray

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.

2 Reviews

Downloads: 2 This Week

Last Update: 2013-04-17
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5

RainLoop Webmail (PHP)

Simple, modern & fast web-based email client

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

Downloads: 1 This Week

Last Update: 2020-01-30
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6

PHPMyWebHosting (PMWH)

PHPMyWebHosting (PMWH) will provide a gui viewed in a browser, which lets you adminstrate postfix-sql-based (mySQL, PostGre) emailaddresses, Apache Virtual Hosts, DNS-zones etc. When completed, PHPMyWebHosting will provide a complete webhosting-Interface

Downloads: 0 This Week

Last Update: 2017-10-08
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7

pfxLogViewer

Postfix log viewer

Fast and user friendly viewer for Postfix logs

Downloads: 0 This Week

Last Update: 2014-10-11
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