Converting old OneNote notebooks to OneNote for Windows 10

straxler14 

I ran into what you are experiencing a long time ago when I first started using OneNote. There were so many iterations of OneNote, first saved the on the hard drive, then OneDrive Personal, then OneDrive for Business Groove.exe, then OneDrive for Business and finally SharePoint. I'm sorry to say that I couldn't find a way to move the notebook pages and I had to re-create my notebooks too after I found out they weren't syncing and then became corrupt. In my case I was lucky that I still had the old OneNote 2016 on my computer and with some of my notebooks, I could open them, copy the pages to a new notebook and then stopped using the old notebooks all together. I don't have a fix for you because I don't think there is one. When you create notebooks, if you are a corporate user, the best thing I can tell you is to create separate notebooks and then save them to OneDrive for Business and then you should be safe for awhile until Microsoft makes another change to OneNote.  I really like OneNote, but I hate these iterations with no way to move old notebook except by re-creating them.

I have called Microsoft Office support in the past for help with OneNote and they weren't able to give me any fix either except to keep recreating the notebooks over and over again.  Not great when you have lots of sections and even more pages.  Sorry I couldn't help you with a fix.