A Microsoft file hosting and synchronization service.
Try this in order:
- Check whether the notebook still exists in OneDrive.
- Go to the OneDrive home page and look through folders such as Documents or Notebooks.
- If the notebook is missing there, OneNote cannot open it because the file may have been deleted or moved.
- If the notebook is still present, open it from OneDrive.
- On the iPhone, manually force a sync of open notebooks.
- In OneNote, pull down the Notebooks list.
- A spinning progress indicator should appear while OneNote re-syncs open notebooks.
- To sync only the current notebook, pull down the section list or page list.
- Re-open any notebooks that may have been closed.
- In OneNote on iPhone, tap More Notebooks at the bottom of the notebooks list.
- Tap the notebooks to open them again.
- If needed, tap Open more from OneDrive.
- Search for notes from within OneNote on iPhone.
- Tap Search on the bottom menu.
- Search by a keyword or phrase from the missing notes.
- If the notes are in a notebook that was closed, they will not appear until that notebook is opened again.
- Sign out of OneNote and sign back in.
- For persistent sync issues on iOS, sign out of all accounts associated with OneNote and then sign in again.
- After signing back in, try the manual sync step again.
- Make sure OneNote is up to date.
- Open the App Store on the iPhone.
- Tap Updates.
- If OneNote appears, tap Update.
- If the notebook cannot be opened in OneNote for the web either, treat it as a storage-location issue.
- If the notebook is stored on OneDrive, check the Service Status page for interruptions.
- If the notebook was moved outside OneNote using file-based sync or folder moves, that can break notebook syncing. OneNote notebooks should be moved and synced through OneNote, not by moving
.onefiles or notebook folders with file sync tools.
- If the notebook was moved or deleted, confirm the notebook address from desktop OneNote if available.
- In OneNote on Windows, go to File > Info to find the notebook address.
- This helps confirm whether OneNote is pointing to an old or missing location.
The key point from the symptoms is that the notebook may no longer exist at the location OneNote expects. Start by verifying the notebook directly in OneDrive, then re-open it from More Notebooks or from OneDrive if it is still there.