Unable to open IRM protected document in Excel Online

[AdminOne]

Hi,

I have an Excel document on SharePoint Online.

I open the document, and set Information Protection to "Confidential" and assign View & Edit Information Protection permissions to a few users.

None of the users can edit the document in Excel Online and are shown the message below:

Why are we seeing this message, when no one has the document open and locked, and we are using Office 365?

Thank you.

[#2]

Hi, @AdminOne,

Thank you for posting your question here.

This error is consistent for an organization that has not completed the steps in the below link, which goes through enabling sensitivity labels for files on the web in SharePoint Online and OneDrive for Business. Can you confirm if this article has been followed?

Enable sensitivity labels for files in SharePoint and OneDrive | Microsoft Learn