One note: Previous notes were lost and synchronization failed.

Hi @SaiyiLuo,

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Welcome to the Q&A community and thank you for reaching out.

I’m really sorry to hear that you’ve lost some of your notebook pages after the sync issue. That can be incredibly frustrating, especially when important notes are involved.

Please note that as a Microsoft Q&A Moderator, working with MacOS is limited on my end when troubleshooting. That said, I’ll do my best to support you through this.

To assist you further, could you please provide a bit more information?

• May I verify that your device on screenshot is MacOs?
• What error message are you seeing? If possible, screenshots would be very helpful.
• Have you tried to check the file on OneNote Web?
• Are you using the same student account that originally accessed the notebook?
• Was your notebook stored locally, online via SharePoint or OneDrive, or both?

In the meantime, here are a few recovery steps you can try:

• Check Deleted Notes: Go to View > Deleted Notes to see if any of the missing pages are still available.
• Check Back up: Go to file > Open backups to see if there any available back up files.
• Check Version History in OneNote Web: Open your notebook in OneNote Online, click the ... (More options) next to the section or page and select Version History to see if previous versions are available.

For more general guidance on recovering OneNote files, you can refer to this article. While it’s written for Windows, many of the steps also apply to Mac users via OneNote Web.

Additionally, you can check this article to locate cached OneNote files on macOS, which may help with recovery.

Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please make sure that you completely understand the risk before retrieving any suggestions from the above link.

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