A family of Microsoft products that enable users to capture, organize, and reuse notes electronically.
I dare to say you made two mistakes:
- Moving the notebooks to Dropbox (works only with OneNote 2016 and with a good chance to ruin your notebooks)
- Moving the notebooks to the OneDrive folder on your computer (this is possible but useless, it omits the necessary conversion to another format)
What you need is the only working way to move notebooks to OneDrive: The File -> Share feature of OneNote 2016.
So move your notebooks manually back to your hard disk and then Share it.
Bernd