SHSelfHostIndex

Courier Mail Server vs Kolab Groupware

A side-by-side comparison of two self-hosted apps from related categories — licensing, setup difficulty, resource needs, and what each one replaces.

Not the right match-up?
CO Courier Mail Server Integrated mail server with IMAP, POP, and webmail VS KO Kolab Groupware Open-source groupware server with mail and calendaring
FeatureCourier Mail ServerKolab Groupware
CategoryMail ServersGroupware
LicenseGPL-3.0AGPL-3.0
LanguageCPHP
Setup difficultyHardHard
Min. RAM512 MB2,048 MB
Deploymentbare-metal, sourcebare-metal, docker
GitHub stars★ 13★ 200
First released20002002
ReplacesMicrosoft ExchangeMicrosoft Exchange, Zimbra

Why pick each one

Choose Courier Mail Server if…

  • Released under the GPL-3.0 license
  • Written in C
  • Lightweight — runs in 512 MB RAM
Courier Mail Server details

Choose Kolab Groupware if…

  • Built on proven components
  • Strong standards support
Kolab Groupware details

Frequently asked questions

Is Courier Mail Server or Kolab Groupware better?

Neither is universally better. Kolab Groupware has the larger community; both share a hard setup difficulty, so the decision comes down to features and licensing.

Are Courier Mail Server and Kolab Groupware free and open-source?

Yes. Courier Mail Server is licensed under GPL-3.0 and Kolab Groupware under AGPL-3.0. Both can be self-hosted at no software cost.

Can I run Courier Mail Server and Kolab Groupware with Docker?

Courier Mail Server: check the project docs for container support. Kolab Groupware: yes.

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