Kolab.

Swiss open-source groupware platform with email, calendar and file management

Facts

Axigen
Romanian enterprise email server with webmail, calendar and instant messaging
RO · commercial
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EGroupware
German open-source groupware platform with email, CRM, project management and more
DE · open-source
↗
grommunio
Austrian open-source groupware platform as an alternative to Microsoft Exchange
AT · open-source
↗
Kopano
Dutch open-source groupware platform with email, calendar and video conferencing
NL · open-source
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Mailcow
German open-source email server platform with Docker-based installation
DE · open-source
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Mailu
Open-source email server in Docker with webmail, anti-spam and antivirus protection
FR · open-source
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Open-Xchange
German open-source email and groupware platform for providers and companies
DE · open-source
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Roundcube
open-source webmail-client with modern interface and plugin-architecture
CH · open-source
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