OpenSMTPD Alternatives

Postfix

Postfix is a mail transfer agent (MTA) that routes and delivers electronic mail. It attempts to be fast, easy to administer, and secure. The software is also known by...

Exim

Exim is a message transfer agent (MTA) developed at the University of Cambridge for use on Unix systems connected to the Internet.

Courier-MTA

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...

Features:

• Email Server
• SMTP

Sendmail

Sendmail is a general purpose internetwork email routing facility that supports many kinds of transfer and delivery methods, including the Simple Mail Transfer Protocol...

Haraka

Haraka is an open source SMTP server written in Node.js which provides extremely high performance coupled with a flexible plugin system allowing Javascript programmers...

Microsoft SMTP Server

Configure SMTP e-mail in IIS when you want to deliver e-mail messages from your site. Mail can be delivered immediately or it can be delivered to a file location on disk...

Features:

• Email Forwarding
• Exchange
• SMTP

NikaMail

NikaMail is a portable, extendable, zero-config email server. It is designed to perform automation tasks, provide access to mailboxes (port 110), serve as a mail...

Features:

• Exchange email
• Email Server
• POP3 Support

Go-Guerrilla

A lightweight SMTP server written in Go, made for receiving large volumes of mail. To be used as a package in your Go project, or as a stand-alone daemon by running the...