OneNote Sync Issues

Dear Ella,

From my research, this error usually affects one section of the notebook rather than the whole thing. Before changing anything, please make sure your recent notes are safe. Open the notebook in OneNote for the web and compare it with the app. If any pages only appear in the app, copy them into another notebook that syncs normally, or into a Word document. Once your notes are backed up, you can try these steps:

• Find the problem section: In OneNote, go to File > Info > View Sync Status, select Sync All, and see whether a particular section is listed with an error.
• Check section names: Rename any recently created sections or section groups that contain special characters, such as +, #, %, or similar. Use only letters, numbers, spaces, or - and _. Then sync again.
• Close and reopen the notebook: Right-click the notebook name and select Close This Notebook. Then open it again from OneNote for the web by selecting Open in Desktop App, and let it finish syncing.
• Move pages to a new section: If one section still won't sync, create a new section in the same notebook and move the pages over a few at a time, syncing after each group. If the error returns after moving a certain page, keep that page aside and recreate its content.
• Clear the OneNote cache: Close OneNote completely. Press Windows + R, type %localappdata%\Microsoft\OneNote\16.0, and press Enter. Open the cache folder and delete its contents, then reopen OneNote. It will rebuild the cache and sync your notebooks from the cloud again. Clearing the cache removes any changes that haven't synced yet, so please only do this after backing up your notes as described above.
• Repair Office: Close all Office apps. Go to Settings > Apps > Installed apps, find Microsoft 365 or Microsoft Office, select the three dots, then choose Modify. If prompted, select Yes, then choose Online Repair > Repair and follow the steps until it finishes. This can take some time, so please keep your PC connected to the internet.

I hope this helps. Looking forward to your reply.

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