Co-authoring in M‑Files: Office Online Server retires

M‑Files checks a document out to one person at a time, so nobody overwrites anyone else’s changes and every version is kept. Most of the time that is the right default. It is the wrong answer when a team has to write in the same document together, which is why co-authoring exists as a separate route.

Until now, M‑Files users have had three options for co-authoring:

• Office Online Server (OOS): an on-premise server.
• CtrlShare: co-authoring in Microsoft 365 through OneDrive for Business.
• Native Microsoft 365 co-authoring in the Business edition of M‑Files, running in M‑Files Cloud.

For anyone running M‑Files outside M‑Files Cloud, that has meant a choice of two: CtrlShare or Office Online Server. With Microsoft retiring OOS, that choice is going away, and it is worth settling on a replacement well before OOS reaches end of support.

What Office Online Server did#

OOS provided browser-based versions of Word, Excel and PowerPoint for on-premise environments. M‑Files integrated with it through WOPI (Web Application Open Platform Interface), which put co-authoring directly in the browser without requiring a full move to the cloud.

Microsoft has scheduled end of support for Office Online Server on 31 December 2026. After that date there are no security patches and no updates, which takes it out of the running for enterprise use. Every M‑Files customer that relies on OOS for co-authoring is affected.

The choice for on-premise M‑Files customers#

If you run M‑Files on-premise, there are two ways forward:

1. Upgrade to M‑Files Business in M‑Files Cloud, which has co-authoring built in.
2. Find an alternative that keeps co-authoring without forcing a full migration.

For plenty of organisations the first option is not practical: compliance requirements, infrastructure already paid for, or a deliberate decision to keep M‑Files under their own control. That is the gap CtrlShare fills.

See what CtrlShare does with a checked-out document, from the vault to OneDrive and back as a new version.

CtrlShare: co-authoring without OOS#

CtrlShare removes the dependency on Office Online Server by using OneDrive for Business and the co-authoring that is already built into Microsoft Office.

• One click. Check a document out from M‑Files to OneDrive for Business.
• The desktop apps. Co-author in the full Microsoft Office desktop experience, not only the more limited web version.
• Permissions from M‑Files. Grant read or write rights and revoke access from the vault.
• External people. Invite them securely, without exposing public links.
• Fewer collisions. With OneDrive doing the co-authoring, version conflicts and lost changes are less likely.

Co-authoring on your own terms#

With no Office Online Server underneath it and no move to M‑Files Cloud required, M‑Files stays where you decided to run it.

If OOS is what your co-authoring runs on today, the date is already set. Check what CtrlShare needs to run, or ask for a trial. We answer the same working day.