Apps similar to Microsoft Exchange include eigen, which is free and open source. Other options are Google Workspace, mailcow: dockerized, Infomaniak kSuite and Kolab. There's no shortage of Mail Servers like Microsoft Exchange, with more than 25 alternatives for Linux, the web, Windows, self-hosting and Mac.
The OX App Suite by Open-Xchange is web-based platform offering a suite of apps like an email client, calendar, contacts magement, cloud storage with synchronization and productivity apps for word processing, spreadsheets and presentations.
Germany
EU
Kolab Now provides a suite of intuitive apps in a user friendly environment to make your day to day online comms easier, smarter and most importantly; secure.
Switzerland
SmarterMail is the only other email server on the market with native support for MAPI, the protocol that powers Exchange and Outlook. That means anything you can do on Exchange you can do with SmarterMail: no plug-ins and no additional software required.
United States
A privacy-first, all-in-one ecosystem that replaces Google Workspace and Creative Cloud. Features encrypted email, cloud storage, and docs, alongside a browser-based 3D animation engine and AI assistant. Your data stays yours.
United States
Is a collaboration suite (messaging and groupware). It is designed to run on open source operating systems such as Linux or BSD. In order to modernize the Citadel platform for the Internet, the Citadel/UX developers added functionality such as shared calendars, instant...
A fully fledged, free email server solution, an open source project (GPL v2).
Use official binary packages from Linux/BSD distributions, with both i386 and x86_64 support.
Easy, fast deployment in LESS THAN 1 MINUTE. View YouTube Video to check how easy it is.
Works on both no.
Blue Mind is a complete solution of company messaging, calendars and collaborative work. It aims to enable you to work daily with comprehensive, useful, efficient and effective tools.
FranceEU
Low cost, easy to use Email Server software for virtual, on-premise, or hosted deployments for companies that want control of their email. Integrated web-mail with doc sharing, Drop Box integration, client and server side encryption.
United Kingdom
OpenChange aims to provide a portable Open Source implementation of Microsoft Exchange Server and Exchange protocols.
Web-based team collaboration suite combining email client, calendar, contact and task tools, CRM, project and file management, file sharing, trouble tickets, Rocket.Chat chat, and Collabora online editing. Offers open source, self-hosted, and SaaS options.
GermanyEU
Real-time email, chat, audio/video calls & conferences, file-sharing, and contacts app with a modern and intuitive UI.
Bosnia & Herzegovina
Open Source Collaboration, providing integration with your existing Linux mailserver, native mobile phone support, Outlook "Look & Feel" webaccess and stable Outlook sharing (100% MAPI).
