Files won't open in desktop app when opening through SharePoint or MS Teams

This usually points to the Windows/Office file-link handoff not being registered correctly, rather than a SharePoint or Teams file problem. Since Office, Windows, Teams, browsers, and even the device were already reinstalled, focus on the file open preference and local Office association path.

1. In Word, Excel, or PowerPoint on Windows, go to File > Options > Advanced > File Open Preference.
   • Set it to Desktop.
   • This preference applies across Word, Excel, PowerPoint, and Outlook.
2. Test from SharePoint or OneDrive with the explicit desktop handoff:
   • Select the file.
   • Choose More > Open > Open in app.
   • For this to work, the OneDrive sync client must be installed/running, and Files on Demand must be enabled.
3. If SharePoint still does nothing, check the SharePoint library behavior:
   • Open the affected library.
   • Go to Gear icon > Library Settings > Advanced settings > Opening Documents in the Browser.
   • If this setting is forcing browser behavior, change it as needed.
4. Reassociate the file type in Windows with the correct Office desktop app:
   • Select Start.
   • Open Control Panel.
   • Go to Programs > Default Programs.
   • Under Set a default for a file type or link type, search for the file type and assign the correct Office app.
   • Repeat for the affected Office file types.
5. If multiple Office versions were ever present on the device, remove the versions not needed and restart Windows. Multiple Office versions can cause files to open in the wrong app or fail to hand off correctly.
6. If the problem is only when opening links from Teams, check the supported scenarios:
   • Desktop opening from Teams requires the file to be a Word, Excel, or PowerPoint file hosted in OneDrive or SharePoint.
   • It must be opened from the Teams desktop app.
   • Teams chat file links can still open in the browser.
   • This feature is supported for Windows users with a qualified Microsoft 365 subscription.
7. If the file opens in the browser but not in desktop, also rule out document-specific issues:
   • A corrupt file or incompatible format can prevent SharePoint from opening it correctly.
   • Download the file and test whether it opens locally.

If none of the above changes the behavior, the remaining supported next steps are the standard Office-side repairs for SharePoint/OneDrive desktop-open issues: clear the Office document cache and repair the Office application.

• Open file links directly in Office desktop apps
• Open a OneDrive or SharePoint file in the desktop app instead of the browser
• Can't open Office files from SharePoint Online
• Open file links directly in Microsoft 365 desktop apps from Teams and classic Outlook
• Double-clicking an Office file fails to open it in the correct Office program
• Fix problems opening documents in SharePoint libraries