How to Use Password Protection in OneNote
If you need to add some protection to your notebook, add a password to one or all of its sections.
The dialog box lets you know there are backup copies of the notebook that aren't protected.
Now that there's a password set, you have the option to lock all the sections if you don't want anything to be seen.
The OneNote Options dialog box opens and you see some password settings. You see here that the default is to have a section stay unlocked for ten minutes after you're done working in it.
You are locked out and can't see the notes.
The section is unlocked and you can now edit the notes once again.
Now if you no longer need a section to be protected, you can remove the password.
You can also change the password here if needed.
The password is removed from the section.