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.

  • Propelling Payments for Software Platforms Icon
    Propelling Payments for Software Platforms

    For SaaS businesses to monetize payments through its turnkey PayFac-as-a-Service solution.

    Exact Payments delivers easy-to-integrate embedded payment solutions enabling you to rapidly onboard merchants, instantly activate a variety of payment methods and accelerate your revenue — delivering an end-to-end payment processing platform for SaaS businesses.
  • Qrvey allows SaaS companies to create richer products and bring them to market faster Icon
    Qrvey allows SaaS companies to create richer products and bring them to market faster

    Our pre-built javascript widgets make it a snap to embed charts, reports and dashboards right into your app

    Qrvey is a low code embedded analytics platform built to help SaaS providers by simplifying the process of putting analytics tools in the hands of all users as fast as possible.
  • 1
    Scrollout F1

    Scrollout F1

    An easy-to-use anti-spam email gateway

    • Designed for Linux and Windows email system administrators, Scrollout F1 is an easy to use, already adjusted email firewall (gateway) offering free anti-spam and anti-virus protection aiming to secure existing email servers, old or new, such as Microsoft Exchange, Lotus Domino, Postfix, Exim, Sendmail, Qmail and others. • Built-in multilayer security levels make configuration effort equal to a car radio. • It combines simplicity with effective protection using powerful open source with additional set of rules & filters. • Available as 64bit: - ISO image (Internet connection required during installation) - install from scratch (Internet connection required during installation). • Minimum Requirements (for 5,000 messages/day): 1 GB of RAM 30 GB storage drive 1 Processor x86/AMD64 1 Ethernet x 1 IPv4 address UDP ports: 53 123 4500 6277 24441 TCP ports: 25 80 443 2703
    Leader badge
    Downloads: 172,097 This Week
    Last Update:
    See Project
  • 2
    Anti-Spam SMTP Proxy Server

    Anti-Spam SMTP Proxy Server

    Anti-Spam SMTP Proxy Server implements multiple spam filters

    The Anti-Spam SMTP Proxy (ASSP) Server project aims to create an open source platform-independent SMTP Proxy server which implements auto-whitelists, self learning Hidden-Markov-Model and/or Bayesian, Greylisting, DNSBL, DNSWL, URIBL, SPF, SRS, Backscatter, Virus scanning, attachment blocking, Senderbase and multiple other filter methods. Click 'Files' to download the professional version 2.8.1 build 23131. A linux(ubuntu 20.04 LTS) and a freeBSD 12.2 based ready to run OVA of ASSP V2 are also available for download. NOTICE: V1 development has been stopped at the end of 2014 (1.10.1 build 16060). Possibly there will be done some bugfixing in future. Please upgrade to V2, which is and will be actively maintained.
    Leader badge
    Downloads: 72,022 This Week
    Last Update:
    See Project
  • 3
    PHPMailer

    PHPMailer

    The classic email sending library for PHP

    PHPMailer – A full-featured email creation and transfer class for PHP. Support for UTF-8 content and 8bit, base64, binary, and quoted-printable encodings. SMTP authentication with LOGIN, PLAIN, CRAM-MD5, and XOAUTH2 mechanisms over SMTPS and SMTP+STARTTLS transports. Validates email addresses automatically. Many PHP developers need to send email from their code. The only PHP function that supports this directly is mail(). However, it does not provide any assistance for making use of popular features such as encryption, authentication, HTML messages, and attachments. Formatting email correctly is surprisingly difficult. There are myriad overlapping (and conflicting) standards, requiring tight adherence to horribly complicated formatting and encoding rules – the vast majority of code that you'll find online that uses the mail() function directly is just plain wrong, if not unsafe!
    Downloads: 301 This Week
    Last Update:
    See Project
  • 4
    OpenPop.NET

    OpenPop.NET

    Robust open source POP3 client and MIME parser written in C#

    .NET library written in C# with a full implementation of a POP3 client. Easy to use but yet powerful. Includes a robust MIME parser backed by several hundred test cases. The easiest way to install OpenPop.NET is via NuGet. In Visual Studio's Package Manager Console, simply enter the following command: Install-Package OpenPop.NET Our homepage (http://hpop.sourceforge.net/) includes examples, documentation and a general introduction for email. For more information, visit our project homepage. Code is hosted on GitHub (https://github.com/foens/hpop).
    Leader badge
    Downloads: 3,734 This Week
    Last Update:
    See Project
  • The Secure Workspace for Remote Work Icon
    The Secure Workspace for Remote Work

    Venn isolates and protects work from any personal use on the same computer, whether BYO or company issued.

    Venn is a secure workspace for remote work that isolates and protects work from any personal use on the same computer. Work lives in a secure local enclave that is company controlled, where all data is encrypted and access is managed. Within the enclave – visually indicated by the Blue Border around these applications – business activity is walled off from anything that happens on the personal side. As a result, work and personal uses can now safely coexist on the same computer.
  • 5
    Windows MBox Viewer

    Windows MBox Viewer

    Windows eml and mbox viewer.

    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.
    Leader badge
    Downloads: 2,178 This Week
    Last Update:
    See Project
  • 6
    Mailspring

    Mailspring

    A faster, leaner email client and fork of Nylas Mail

    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.
    Downloads: 86 This Week
    Last Update:
    See Project
  • 7
    MOSINT

    MOSINT

    An automated e-mail OSINT tool

    MOSINT is the fastest OSINT Tool for emails. It helps you gather information about the target email. Email validation, check social accounts, check data breaches and password leaks, finding related emails and domains, scan Pastebin Dumps. Google Search and DNS Lookup.
    Downloads: 84 This Week
    Last Update:
    See Project
  • 8
    MailHog

    MailHog

    Web and API based SMTP testing

    Inspired by MailCatcher, easier to install. Built with Go, MailHog runs without installation on multiple platforms. Run it from Docker Hub or using the provided Dockerfile. The SMTP server starts on port 1025, the HTTP server starts on port 8025, in-memory message storage. ESMTP server implementing RFC5321. Support for SMTP AUTH (RFC4954) and PIPELINING (RFC2920). Web interface to view messages (plain text, HTML or source). Supports RFC2047 encoded headers. Real-time updates using EventSource. Release messages to real SMTP servers. Chaos Monkey for failure testing. HTTP API to list, retrieve and delete messages. See APIv1 and APIv2 documentation for more information. HTTP basic authentication for MailHog UI and API. Multipart MIME support. Download individual MIME parts. In-memory message storage. MongoDB and file based storage for message persistence. Lightweight and portable. No installation required.
    Downloads: 70 This Week
    Last Update:
    See Project
  • 9
    theHarvester

    theHarvester

    E-mails, subdomains and names

    theHarvester is a very simple to use, yet powerful and effective tool designed to be used in the early stages of a penetration test or red team engagement. Use it for open source intelligence (OSINT) gathering to help determine a company's external threat landscape on the internet. The tool gathers emails, names, subdomains, IPs and URLs using multiple public data sources.
    Downloads: 58 This Week
    Last Update:
    See Project
  • RMM Software | Remote Monitoring Platform and Tools Icon
    RMM Software | Remote Monitoring Platform and Tools

    Best-in-class automation, scalability, and single-pane IT management.

    Don’t settle when it comes to managing your clients’ IT infrastructure. Exceed their expectations with ConnectWise RMM, our MSP RMM software that provides proactive tools and NOC services—regardless of device environment. With the number of new vulnerabilities rising each year, smart patching procedures have never been more important. We automatically test and deploy patches when they are viable and restrict patches that are harmful. Get better protection for clients while you spend less time managing endpoints and more time growing your business. It’s tough to locate, afford, and retain quality talent. In fact, 81% of IT leaders say it’s hard to find the recruits they need. Add ConnectWise RMM, NOC services and get the expertise and problem resolution you need to become the advisor your clients demand—without adding headcount.
  • 10

    milter manager

    Protects you from spam mails and virus mails effectively with milter

    This project has been moved to https://milter-manager.osdn.jp/ milter manager protects you from spam mails and virus mails effectively with milter. milter manager has embedded Ruby interpreter to control milters flexibly. milter manager can be used with Sendmail on Postfix on Ubuntu, CentOS, FreeBSD and so on.
    Leader badge
    Downloads: 4,274 This Week
    Last Update:
    See Project
  • 11
    Blat - Windows Command Line SMTP Mailer
    Blat - A Windows (32 & 64 bit) command line SMTP mailer. Use it to automatically eMail logs, the contents of a html FORM, or whatever else you need to send.
    Leader badge
    Downloads: 944 This Week
    Last Update:
    See Project
  • 12
    King Phisher

    King Phisher

    Phishing Campaign Toolkit

    King Phisher is an open source tool that can simulate real world phishing attacks. It has an easy-to-use, flexible architecture that allows for full control over both emails and server content. It is useful for running awareness campaigns and training, and can only be used for legal applications when the explicit permission of the targeted organization has been obtained.
    Downloads: 39 This Week
    Last Update:
    See Project
  • 13

    mailsend

    A program to send mail via SMTP from command line

    mailsend is a simple command line program to send mail via SMTP protocol. It can send a piece of alert mail from a program in a networked Windows machine. It's feature-filled, cross-platform, free and open source, and does not use any config file.
    Downloads: 32 This Week
    Last Update:
    See Project
  • 14
    Outlook CalDav Synchronizer

    Outlook CalDav Synchronizer

    Sync Outlook with Google, SOGo or any other CalDAV / CardDAV server

    Free Outlook Plugin, which synchronizes events, tasks and contacts between Outlook and Google, SOGo, NextCloud, Horde or any other CalDAV or CardDAV server. Supported Outlook versions are 2021, 2019, 2016, 2013, 2010 and 2007 and Office 365 for Desktop. This project was initially developed as a master thesis project at the University of Applied Sciences Technikum Wien, Software Engineering Degree program. Outlook CalDav Synchronizer is Free and Open-Source Software (FOSS), still you can support the project by donating on Sourceforge or directly within the About dialog of our Plugin. Contact us for enterprise support at https://caldavsynchronizer.org/enterprise/contact
    Leader badge
    Downloads: 614 This Week
    Last Update:
    See Project
  • 15
    SquirrelMail
    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.
    Leader badge
    Downloads: 588 This Week
    Last Update:
    See Project
  • 16
    DavMail POP/IMAP/SMTP/Caldav to Exchange
    Ever wanted to get rid of Outlook ? DavMail is a POP/IMAP/SMTP/Caldav/Carddav/LDAP gateway allowing users to use any mail client with Exchange and Office 365, even from the internet through Outlook Web Access on any platform, tested on MacOSX, Linux and Windows
    Leader badge
    Downloads: 511 This Week
    Last Update:
    See Project
  • 17
    GO Contact Sync Mod

    GO Contact Sync Mod

    Sync Outlook contacts and calendars with Google

    Please install the latest version >4.0, because it uses the new Google People API. The Google Contacts API is now deprecated and is scheduled for sunset on June 15, 2021. GO Contact Sync Mod synchronizes your Microsoft Outlook contacts with your Google Mail address book, including pictures, categories and contact notes. It also syncs your Outlook Calendar Appointments on demand to Google Calendar. This Mod fork adds many enhancements and bug fixes to the obviously dead project 'Go Contact Sync'. Minimum requirement for GO Contact Sync Mod is .NET 4.7.2 and Windows 7 (32 or 64 bit).
    Leader badge
    Downloads: 413 This Week
    Last Update:
    See Project
  • 18
    Elastix

    Elastix

    Unified Communications Server

    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.
    Leader badge
    Downloads: 391 This Week
    Last Update:
    See Project
  • 19
    MsgViewer
    MsgViewer is email-viewer utility for .msg e-mail messages, implemented in pure Java. MsgViewer works on Windows/Linux/Mac Platforms. Also provides a java api to read mail messges (msg files) programmatically.
    Leader badge
    Downloads: 482 This Week
    Last Update:
    See Project
  • 20
    trixbox CE is an easy to install, VOIP phone system based on the Asterisk PBX. trixbox is designed for home or office use. trixbox CE includes CentOS linux, mysql, and all the tools needed to run a business quality phone system. (formerly asterisk@home)
    Leader badge
    Downloads: 301 This Week
    Last Update:
    See Project
  • 21
    Tutanota

    Tutanota

    Open source email service with a strong focus on security and privacy

    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.
    Downloads: 13 This Week
    Last Update:
    See Project
  • 22
    E-MailRelay

    E-MailRelay

    SMTP email proxy and relay server

    E-MailRelay is a simple SMTP proxy and relay MTA, written in C++, for Linux and Windows. As a proxy all messages can be passed through a user-defined program, such as a spam-filter, which can drop, readdress, or edit messages as they pass through.
    Leader badge
    Downloads: 282 This Week
    Last Update:
    See Project
  • 23
    Mail-in-a-Box

    Mail-in-a-Box

    Take back control of your email with this mail server in a box

    Mail-in-a-Box helps individuals take back control of their email by defining a one-click, easy-to-deploy SMTP+everything else server, a mail server in a box. Mail-in-a-Box lets you become your own mail service provider in a few easy steps. It’s sort of like making your own gmail, but one you control from top to bottom. Technically, Mail-in-a-Box turns a fresh cloud computer into a working mail server. But you don’t need to be a technology expert to set it up. Our goals are to make deploying a good mail server easy, promote decentralization, innovation, and privacy on the web, have automated, auditable, and idempotent configuration, not make a totally unhackable, NSA-proof server, and not make something customizable by power users. Mail-in-a-Box turns a fresh Ubuntu 18.04 LTS 64-bit machine into a working mail server by installing and configuring various components. It is a one-click email appliance. There are no user-configurable setup options. It "just works."
    Downloads: 11 This Week
    Last Update:
    See Project
  • 24
    PostfixAdmin
    PostfixAdmin is a Web Based Management tool created for Postfix. It is a PHP based application that handles Postfix Style Virtual Domains and Users that are stored in MySQL, PostgreSQL or SQLite
    Leader badge
    Downloads: 243 This Week
    Last Update:
    See Project
  • 25
    The Courier mail transfer agent (MTA) is an integrated mail/groupware server based on open commodity protocols such as ESMTP, IMAP, POP3, LDAP, SSL, and HTTP. Courier provides ESMTP, IMAP, POP3, Webmail, calendaring, and mailing list services.
    Leader badge
    Downloads: 234 This Week
    Last Update:
    See Project
  • Previous
  • You're on page 1
  • 2
  • 3
  • 4
  • 5
  • Next