Microsoft Exchange Server is described as 'messaging and collaborative software product developed by Microsoft. It is part of the Microsoft Servers line of server products and is widely used by enterprises using Microsoft infrastructure solutions' and is a Mail Server in the Social & Communications category. There are more than 25 alternatives to Microsoft Exchange Server for a variety of platforms, including Linux, Online / Web-based, Windows, Self-Hosted solutions and Mac. The best alternative is Kopano, which is both free and Open Source. Other great apps like Microsoft Exchange Server are Google Workspace (Paid), hMail Server (Free, Open Source), Zentyal (Paid, Open Source) and mailcow: dockerized (Free, Open Source).
Fast, safe, heavy mail solution. Web-client access, LAN or WAN self-hosted server, maintenance-free design. No Windows server and database server required, unlimited mail accounts, storage, attachment size, custom logo. Free for commercial use.
The Mercury Mail Transport System is a mail server that sends and receives messages on behalf of a group of users on a machine or local area network. Messages from the outside world are received by Mercury and delivered to the users, who can access it at any later point.
Sanwhole Exchange is a server running iMail, iPress and iStore services. iMail is an enterprise-class email server does Microsoft Exchange and Gmail work. iPress sets blog, forums and tickets in one. iStore is an online store.
Online Collaboration with Chat and Online Office.
Is developed as open source software in Germany, offered as free community version and as commercial version. Operation as self-hosted or as SaaS from the computer centre.
Xeams is a secure and powerful mail server for that includes a powerful spam filtering engine that eliminates up to 99% of junk email right out of the box. The software offers a flexible approach to email, making it a very user friendly server.