Open the Notebook in recents or click on My Notebooks.

If you click on the Notebook directly skip to Step 10.

Click on OneNote, or if you can see the Notebook you want to open in your Recents, click on that.

Click on the Office 365 Tile in home.Scotch or home.PLC.

Please put in your UID and select Sign in.

You may be redirected so the Scotch or PLC Sign in Page.Then, select OneNote and then Sign In.Search for Office in Keychain Access and delete the all keychain entries that look like the ones in the screenshot below ( don’t delete any with “Exchange” in them).Open Keychain Access using the Spotlight search feature ( press spacebar and command).At the top click OneNote, then click Quit OneNote. Click OneNote and then select Sign Out.Right click on the affected Notebook, then click Close this Notebook.If this still didn't solve your issue you may have to reset your Office Keychain, in Keychain Access. Wait for it to open in your desktop application. Click on the Notebook that was having difficulty syncing.Open a web browser, and go to home.Scotch or Home.PLCand click on the Office 365 Tile.If a OneNote Notebook is not syncing, Right Click (Control-Click) on the affected Notebook.If you are unsure how, refer to the following guide: How do I run updates on my Mac at Scotch? Ensure you have Installed All Available Updates for your Mac.To do so, follow this guide: What should I do if my Microsoft Applications are playing up? To fix this you will have to close OneNote and exit the web interface (on your internet browser). OneNote may be experiencing difficulties if your Notebooks are not syncing.

Onenote class notebook never syncs