OneDrive files opened from Finder not recognized as cloud files on Mac

Office for Mac: OneDrive files opened from Finder no longer recognized as cloud files – AutoSave disabled

Hi everyone,

I am experiencing a persistent issue with Microsoft 365 for Mac and OneDrive that started suddenly around August 10, 2026. The same setup and workflow had worked without problems for more than two years before that.

Problem

My Office files are stored in OneDrive and synchronized to my Mac via the standard macOS File Provider.

When I open an Excel or Word file by double-clicking it in Finder, the Office application opens the file, but it apparently does not recognize it correctly as a OneDrive/cloud file.

For example:

• AutoSave is disabled
• real-time co-authoring does not work as expected
• when I try to enable AutoSave manually, Office behaves as if the file were local and asks me to upload/save it to OneDrive – even though the file is already stored and synchronized in OneDrive

However, if I open the exact same file from within Excel or Word via the OneDrive/Online Locations option, everything works correctly:

• AutoSave is enabled immediately
• co-authoring works
• changes made by another user appear in real time

This behavior is reproducible with multiple files and affects both Excel and Word, so it does not appear to be an issue with one particular workbook or application.

Environment

• MacBook Air M2
• current macOS version
• current Microsoft 365 version
• current OneDrive version
• OneDrive Personal
• files synchronized through the standard macOS File Provider

I have also tested opening files directly from:

~/Library/CloudStorage/OneDrive/...

The result is the same: when opened from Finder, Office does not appear to recognize the file correctly as a cloud file and AutoSave remains disabled.

Troubleshooting already performed

I have already:

• completely reset and reconfigured OneDrive
• allowed OneDrive to fully resynchronize
• verified the files and folders in OneDrive on the web
• confirmed that OneDrive reports everything as synchronized
• restarted Finder and macOS
• removed and recreated Finder shortcuts/favorites
• tested without Finder favorites or aliases
• tested directly from ~/Library/CloudStorage/OneDrive
• updated macOS
• updated all Microsoft 365 applications
• updated OneDrive

None of these steps changed the behavior.

Key diagnostic result

The following comparison is consistently reproducible:

Finder → OneDrive file → double-click → Excel/Word

→ AutoSave OFF
→ file appears not to be recognized as an active OneDrive cloud document
→ co-authoring does not work correctly

Excel/Word → Open → OneDrive/Online Locations → same file

→ AutoSave ON immediately
→ cloud functionality works
→ co-authoring works correctly

This suggests that OneDrive synchronization itself is functioning correctly. The issue seems specifically related to the handoff between macOS Finder / Apple File Provider / OneDrive and Microsoft 365 for Mac when a OneDrive file is opened from Finder.

Important detail

This is not a workflow that has never worked on macOS.

For more than two years, we routinely opened our synchronized OneDrive Word and Excel files directly from Finder. Office recognized them as cloud files, AutoSave was available, and collaborative editing worked normally.

The behavior changed suddenly around August 10, 2026, without us intentionally changing the OneDrive folder structure or our workflow.

Question

Has anyone else encountered this recently?

In particular:

1. Is this a known regression in Microsoft 365 for Mac, OneDrive for Mac, or their integration with Apple's File Provider?
2. Why would Office recognize a file as a OneDrive cloud document when opened through the application's Online Locations, but not when the exact same synchronized file is opened from Finder?
3. Is there a way to reset or repair the Microsoft 365/OneDrive cloud-file recognition or File Provider integration without resetting the entire OneDrive again?
4. Are there any relevant logs, caches or diagnostics that could show why Office considers a Finder-opened OneDrive file to be local?

Opening every document through the Office application's Online Locations is a possible workaround, but it is not a practical long-term solution when working with a larger shared folder structure in Finder.

I have already contacted both Apple Support and Microsoft Support. Apple referred me to Microsoft, and Microsoft Support subsequently recommended that I raise the issue here in the Tech Community.

Any insight from Microsoft staff, MVPs or others familiar with Microsoft 365 for Mac, OneDrive and the macOS File Provider would be greatly appreciated.