Dear @Robin Smitz,
Good day! Welcome to Microsoft Q&A forum!
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Based on your description, I understand that you’re encountering an error when using the “Send to OneNote” feature: Cannot save this item to a shared notebook due to sensitivity label restrictions. Please save it to personal notebook. This issue occurs only in the New Outlook and the Web Version, while the feature works as expected in Classic Outlook.
I sincerely apologize for the inconvenience this has caused.
Regarding the situation, I tested this on my side and encountered the same error as you.
When the location to save the meeting details in OneNote is [YourName] @ [CompanyName]: The error code would be: Cannot save this item to a shared notebook due to sensitivity label restrictions. Please save it to personal notebook.

I have also tested this on my colleagues' devices and experienced the same error.
Therefore, I tried to save it to my personal notebook instead.
When I add a new personal notebook named "Test error" in OneNote, I could save the meeting details there.


You could refer to this thread for more helpful information as many other users also run into this error: https://learn.microsoft.com/en-us/answers/questions/5574077/sending-emails-from-outlook-to-onenote-through-app
Currently, there are no known errors associated with this feature in the Microsoft 365 Admin Center.
However, when other users have experienced the same error, even from your IT partners in other tenants, I strongly recommend Reporting an issue in Microsoft 365 Admin Center > Health > Service health > Report an issue so that the Product team would be aware of this issue and investigate further to fix it.

For further assistance, Microsoft’s support team could help with this. A Technical Support Engineer can perform a remote session to investigate the situation, verify the backend configurations, and run any necessary synchronization tools to resolve the problem. If the issue requires further attention, they can escalate it to a specialized team for deeper analysis.
As forum moderators, we don’t have access to the detailed logs or backend systems needed to troubleshoot this effectively due to privacy and security constraints. For that reason, the most efficient solution would be to contact Microsoft’s support team directly.
For the standard procedure outlined above, Office 365 Global Administrators may need to contact the Office 365 support team by submitting a service request.
Here’s what your Office 365 Global Admin should do next:
Submit a Service Request: The Global Admin should create a service request with Microsoft support to get advanced technical assistance and diagnostics. For detailed instructions on how to get support, please refer to Get support - Microsoft 365 admin.
Note: After creating the support ticket, please kindly let me know the ticket number so I could also track its process to help you with this situation.
Thank you for your kindness and patience!
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