Hi @StefanoPadovan,
Thank you so much for clarifying about your personal OneDrive for Business. I’d like to share some additional insights I found on why contentStream works with communication sites but not with your personal OneDrive for Business:
Based on my research, the contentStream endpoint behaves differently from standard DriveItem calls. Instead of routing requests through the Microsoft Graph Files Service which normally handles token translation and backend compatibility, the contentStream endpoint establishes a direct streaming channel to the underlying file storage backend.
The error code 00000003-0000-0ff1-ce00-000000000000 refers to the SharePoint resource GUID. When you use contentStream on a communication site, this design works because SharePoint site libraries accept Graph access tokens for direct file retrieval. However, for OneDrive for Business, the backend enforces a stricter audience check. A Graph-scoped token won’t pass because the request bypasses Graph and goes straight to SharePoint, which expects a SharePoint-scoped token. This mismatch causes the error 401 “Invalid audience” error you observed.
Currently, as I checked, Microsoft does not provide documentation stating that contentStream is supported for OneDrive items, nor is there a documented mechanism to supply a SharePoint Online token to this API. This strongly suggests the behavior is by design rather than a configuration or permissions issue.
Therefore, I suggest you raising this request on the Microsoft Feedback Portal. This is where the engineering team reviews customer input to improve Microsoft products. The more voices advocating for this change, the higher the chances that the API will be updated.
Thank you for your understanding.