Sendmail is described as 'General purpose internetwork email routing facility that supports many kinds of transfer and delivery methods, including the Simple Mail Transfer Protocol (SMTP) used for email transport over the Internet' and is a Mail Server in the online services category. There are more than 25 alternatives to Sendmail for a variety of platforms, including Linux, Self-Hosted, Windows, Mac and BSD apps. The best Sendmail alternative is Postfix, which is both free and Open Source. Other great apps like Sendmail are Zentyal, Mail-in-a-box, Zimbra Collaboration Suite and Microsoft Exchange.
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 its former names VMailer and IBM Secure Mailer.
Integrates native Active Directory and all essential network services, including domain, mail, gateway, infrastructure, and security roles, for SMBs, offering web-based management, centralized authentication, file server, VPN, and firewall in a single Linux platform.
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Zimbra Collaboration is an open, secure collaboration tool for email, calendaring, tasks and more. With the most innovative web application available today, Zimbra boosts the productivity of users on any desktop and dramatically reduces TCO compared to legacy platform vendors.
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Exchange business-class email helps increase user productivity while protecting your data. Get it as a hosted service or run it on your servers.
United States
Exim is a message transfer agent (MTA) developed at the University of Cambridge for use on Unix systems connected to the Internet.
OpenSMTPD is a FREE implementation of the server-side SMTP protocol as defined by RFC 5321, with some additional standard extensions. It allows ordinary machines to exchange e-mails with other systems speaking the SMTP protocol.
Real-time email, chat, audio/video calls & conferences, file-sharing, and contacts app with a modern and intuitive UI.
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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, and mailing list services within a single, consistent, framework.
A small Mail Transport Agent (MTA), designed for home and office use. Part of DragonFly BSD , it accepts mails from locally installed Mail User Agents (MUA) and delivers the mails either locally or to a remote destination.
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