To share files from OneDrive in File Explorer, follow these instructions:
Note: this is different from sending a file to a user. This will allow all the users to make changes to this document, and it will reflect in the document itself. When you send a file to a user, you attach the file to the email. This will make the document standalone and any changes made to it will not affect the original document in OneDrive.
Make sure you have access to OneDrive in File Explorer.
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