Schleswig-Holstein, a northern German state, has successfully migrated its entire government email system away from Microsoft products to open-source alternatives, marking a key milestone in its digital sovereignty initiative.
This initial phase saw the state replace Microsoft Exchange and Outlook with Open Xchange and Mozilla Thunderbird. The shift, completed on October 2, affected government, judicial, and police departments.
More than 40,000 mailboxes were converted during the six-month process. This involved over 100 million emails and calendar entries. Approximately 30,000 public servants participated in the transition.
The move underscores a broader German effort to reduce reliance on proprietary software and regain control over digital operations. Such transitions often present complexities, including years of dependency on specific applications, closed data formats, and established employee habits.
Authorities collaborated closely with open-source providers. This ensured compatibility, support, and scalability for the new systems. The conversion was planned as a gradual process to minimize operational disruptions and facilitate staff training.
Planning for this comprehensive project has been underway for several years. Operational implementation began in 2024 with the adoption of LibreOffice as the standard office suite across government systems. Microsoft Office is subsequently being removed from some government computers.
Future phases for Schleswig-Holstein include replacing SharePoint with Nextcloud. The state also plans to complete the full transition to LibreOffice in all government offices. A final step will involve migrating operating systems from Windows to a Linux distribution.