Denmark ends Collabora Office replacement trial after file problems

Denmark has ended a trial of Collabora as a possible replacement for Microsoft Office after the software struggled with existing Office documents. The pilot involved 38 ministry employees and exposed a familiar problem for public bodies trying to move away from proprietary office formats: compatibility is not a minor detail when the files already in circulation are built around someone else’s software.¹

The trial was designed to test whether Collabora could reduce the Danish government’s dependence on Microsoft’s office suite. During the pilot, some Microsoft Office files using the OOXML format reportedly opened with pages missing or blank in Collabora. The project was paused during elections and has now been cancelled, leaving Denmark’s next move unclear.²

OOXML is not a single, simple file experience. Microsoft’s formats are documented, but real-world documents can contain application-specific behaviour, unusual layouts, embedded objects, fonts and features that do not translate cleanly between office suites. A document that appears ordinary to its author can therefore become a migration test in disguise.

That does not make an alternative suite useless. Collabora describes its products as open-source editors designed to work with Microsoft and open document formats, and its own site highlights interoperability as a core part of the product. The Danish pilot instead shows how difficult it is to guarantee that compatibility at the scale of an organisation with years of inherited files.³

The result is a setback for Denmark’s digital-sovereignty ambitions, not proof that every open-source office migration will fail. A successful switch would need representative files, careful conversion testing, support for edge cases and a plan for documents that cannot be made identical across applications. It would also need to separate routine documents from the handful of templates or workflows that are genuinely business-critical.

Our opinion

The important lesson is less “open source cannot replace Office” and more “file compatibility has to be treated as infrastructure”. A 38-person pilot is small, but it is large enough to reveal whether staff can open the documents they actually need. If pages arrive blank, the migration has failed its first practical test regardless of how attractive the licensing or sovereignty argument looks on paper.

Denmark’s experience also explains why these projects often move more slowly than political announcements suggest. Replacing a suite means replacing habits, templates, macros, document checks and support processes as well as installing new software. The next attempt, whether it uses Collabora or another option, will need to start with a brutally honest inventory of the files that cannot break.

For now, the country has learned that choosing a replacement is the easy part. Making every old document behave predictably is the work.