OneNote for Mac crashes on Launch

Question:

Today, when using OneNote for Mac my MacBook Pro crashed. After rebooting, it told me OneNote had caused the crash. Now, everytime I open OneNote, the app crashed immediately. I've tried re-installing through the App Store and removing caches but it keeps crashing on start.

What to do? Most important is there are a lot of unsynced changes I cannot afford to lose...

 

Solution:

1. Delete this folder: ~/Library/Containers/com.microsoft.onenote.mac
2. Delete this folder: ~/Library/Group Containers/UBF8T346G9.Office
3. Open up “Keychain Access” app on your Mac, and search for “MicrosoftOffice”. If OneNote recognized that you signed in, you will have an entry with a long name. Delete it.
4. Restart your computer.
5. Try launching OneNote and signing in again.