Hi,
We may first try to start OneNote with /safeboot command and then try the "Delete Notebook Cache" and "Delete Settings" options to see the result. To do this, press Windows key + R to open the Run command, type onenote /safeboot and press Enter.
In the opened dialog, click Delete Notebook Cache button first to see the result.
Note: This action will close all opened notebooks in your OneNote, youll have to reopen the notebooks. Please make sure you have all your notebooks synced before this action, youll lose your unsynced changes after this.
If above doesn't work, we can then try click the Delete Settings button to see the result. If this issue is caused by corrupt settings file, this option will fix it. When OneNote starts, it will have default settings, but you can change them later.
Please let me know the result.
Regards,
Steve Fan
TechNet Community Support