I found these happen to me if I leave OneNote open, and put the computer to hibernate / sleep mode. Somehow when the computer awake from sleep, OneNote will failed to sync due to the credentials is out of sync.
To avoid this I always close OneNote before putting the computer to sleep and often I simple shutdown the computer.
The fix to this is simply delete the cached credential used by OneNote to connect to server for synchronization, and re-login.
To do this, follow the following steps (Make sure you close OneNote before you proceed):
- Go to "Control Panel" > "User Accounts and Family Safety"
- "MicrosoftAccount" - the credential you use to login to Windows
- "OneDrive Cached Credential"