I'm getting a 0xE01901F7 and the same code, but this added on bdf5i something to do with my notebook not syncing. I need help to fix it.

Copy any recent unsynced notes to a safe location first, then open the notebook in OneNote for the web to determine whether error 0xE01901F7 (bdf5i) is confined to the Windows app or affects the cloud copy.

Microsoft’s available error documentation does not identify that exact code, so avoid deleting the cache, signing out, reinstalling OneNote, or closing the notebook until unsynced content is protected; these actions can cause data loss during a sync failure.^1^

1. Protect recent notes

On every computer or device where this notebook has been edited:

1. Open pages containing changes that might not have synced.
2. Copy their contents into a document outside OneNote, or copy the pages into a new notebook that successfully syncs.
3. Do not delete the original pages yet.

2. Check the cloud copy

1. In the OneNote desktop app, select File > Info.
2. Under the affected notebook, right-click the notebook URL and select Copy.
3. Paste that URL into a browser and open it.
4. Sign in with the Microsoft account that owns or has access to the notebook.
5. Check whether the latest pages and edits appear.

This separates the recovery into two cases.^1^

If the latest notes appear in the browser

The cloud notebook is current, so reset its connection to the Windows app:

1. Return to File > Info in OneNote.
2. Next to the affected notebook, select Settings > Close.
3. In the browser copy of the notebook, select Open in Desktop App.
4. Wait for the notebook to load, then select File > Info > View Sync Status > Sync Now.

Closing and reopening is appropriate only after confirming that the browser contains the latest content or after backing up anything missing from it.

If the browser has an older copy or the notebook will not open

Return to the computer or device containing the newest notes:

1. Select File > Info > View Sync Status.
2. Expand the affected notebook and note whether a yellow warning identifies one section.
3. Select Sync Now.

If only one section fails:

1. Create a new section in the same notebook.
2. Right-click each page in the failing section and select Move or Copy.
3. Copy, rather than move, the pages into the new section.
4. Press Shift+F9 and wait for synchronization to finish.
5. Confirm that the copied pages appear in the browser before deleting anything from the old section.

Microsoft documents copying pages into a new section as the workaround when one section has stopped syncing.^1^

If the entire notebook fails but other notebooks still sync, create a new notebook on OneDrive and copy sections into it one at a time. Check the browser after each section so the problematic section can be isolated without risking the rest of the notebook.

If none of the notebooks sync

Install available Office updates, verify Internet access, and check whether OneDrive itself is reporting a sync problem.^2^ For a notebook stored on an organization’s SharePoint site, contact its Microsoft 365 administrator because access or service-side investigation may be required.

When requesting further support, include:

• Full error: 0xE01901F7 (bdf5i)
• Whether the notebook opens in the browser
• Whether recent edits appear there
• Whether one section or the entire notebook is affected
• The OneNote version shown under File > Account > About OneNote

References

1. Fix issues when you can't sync OneNote | Microsoft Support
2. Fix OneDrive sync problems | Microsoft Support