2020-10-13, Ended Support OneNote 2013 Connectivity to Microsoft 365 Services, 2023-4-11, Ended Support Entirely
2010-10-13, Ended Support for OneNote 2013 Connect to Microsoft 365 Services
Microsoft is no longer testing or modifying whether OneNote 2013 can connect to OneDrive.com.As a result, OneNote 2013 will eventually fail to connect to OneDrive.com.
Now, 2023.4.1, OneNote 2013 can no longer log in to Microsoft school or work accounts, but can still log in and sync Microsoft personal accounts and notebooks.
There will come a day when OneNote 2013 won't be able to log in to your Microsoft personal account.
2023-4-11, Microsoft Ended Support for OneNote 2013 Entirely
Microsoft has completely ended support for OneNote 2013, including security issues, and is no longer fixed.