Onenote notebook broken

To recover data from a broken OneNote notebook using backups, use OneNote’s built‑in backup restore feature. This requires that backups were previously created (automatic or manual).

Follow these steps in the OneNote desktop app (OneNote for Microsoft 365 / 2016 / 2021 / 2024):

1. Open the notebook that is reported as read‑only or broken.
2. Select File > Info > Open Backups.
3. In the Open Backup dialog box:
   • Double‑click the folder for the notebook that matches the broken one.
   • Select the section backup file (.one) you want to restore, then choose Open.
4. OneNote will show the backup section under Open Sections.
5. To restore content:
   • To restore an entire section: right‑click the backup section tab and select Move or Copy.
   • To restore specific pages: right‑click the page tab(s) and select Move or Copy.
6. In the Move or Copy dialog, choose the destination notebook/section (for example, the current broken notebook or a new notebook) and click Copy.
7. After confirming the content is restored, right‑click the backup section and select Close so it doesn’t get confused with the active notebook.

If the notebook was stored locally (not only in the cloud), another path to backups in Office 2016/desktop is:

1. Open the notebook.
2. Go to File > Info > Open Backups.
3. In the backup list, open the relevant notebook folder and section backup.
4. Use Move or Copy to place the recovered pages/sections back into the active notebook.

Once restored into an active notebook, the data will sync again (if the notebook is on OneDrive/SharePoint) and the restored content will be available across devices.

References:

• Restore notes from a backup
• Recover deleted notes