Best Open Source Post-Office Software 2026

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Browse free open source Post-Office software and projects below. Use the toggles on the left to filter open source Post-Office software by OS, license, language, programming language, and project status.

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1

hMailServer

hMailServer is a SMTP/POP3/IMAP server for Windows. Data is stored in MySQL/MSSQL database and is easily accessed using the COM library. Project info, trackers and downloads has moved to www.hmailserver.com.

1 Review

Downloads: 23 This Week

Last Update: 2015-08-24
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2

Columba

Columba is an email client written in Java, featuring a user-friendly graphical interface with wizards and internalionalization support. Its a powerful mail management tool with features to enhance your productivity and communication.

5 Reviews

Downloads: 3 This Week

Last Update: 2016-03-01
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