Next, you need to navigate into its respective folder (if the notebook is in a folder itself). This is great, but we would like to use the user interface right? So the easiest way is to navigate to the specific document library, where the file is stored, for example:

This functionality is what OneNote Class Notebooks seem to use on the background. OneNote API gives us the ability to modify the permissions through RESTful calls. one files as sections inside (you can learn more details here). Section groups are represented as folders as well with.

Read on to learn how! Basically, when you create a OneNote notebook in a document library, what really happens is that a folder is created there with the notebook’s name and then the sections (. While this functionality isn’t for some reason available directly from the UI, it is definitely possible. When you have a OneNote notebook shared with an entire group or site in SharePoint (or with few people in OneDrive for Business) you might want to be able to set permissions on a section or section-group level. Protip: Assigning section level permissions in OneNote

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