This may be really a OneDrive or a PowerPoint issue, but here is the scenario. User 1 shares a modern attachment from her OneDrive to a DL. Everyone appears to work fine that directly receives the email with the linked OneDrive attachment. One of those recipients forwards that email to his team. These recipients do not have access to the file. When one of them tries to open the attachment on Windows, PowerPoint just opens, but never responds or shows an error. On the Mac, the user gets a "Not Authorized" error (as expected). Why is Windows not throwing an error? We do not expect this user to be able to open since they do not have access, but an error would be nice. Thoughts?