Dear GinliC,
Good day! Thank you for posting to Microsoft Community. We are happy to help you.
Normally, when users select the file in Teams or in the browser, they can choose the option to open the file in the Office application. If you want to let them open files in Office applications by default, please check the following settings.
For SharePoint, at the document library level, you can go to Library settings>Advanced settings>Open in the client application.
If you want to enable the feature at the site collection level, please go to Site information>View all site settings>Site Collection features> activate the feature “Opening Documents in Client Applications by Default”
For the Teams client, please set the setting as shown below:
We look forward to your response. Thanks for your cooperation.
Sincerely,
George | Microsoft Community Moderator
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