OneNote Intune Sync issue with Error Code: 0xE4010643 c12qc

Hi @AC,  

I hope you're having a good day so far. 

I'm reaching out again to follow up on your issue and check if everything has been resolved. My goal is to ensure your experience remains smooth and hassle-free. If you're still encountering any problems or have run into new challenges, please let me know which steps you're currently stuck on and happy to provide further help whenever you need it.  

If you have any further questions, feel free to tag me in your reply so I can assist you directly. 

Looking forward to your update. 

Hi @AC, 

Hope things are running smoothly on your end. 

Following up on the support thread we've been working on. I hope the information I shared in my previous answer resolve the issue you were facing. If you are still facing the same issue or need assistance with anything else, kindly respond to this email, and I will be happy to help. 

We want to make sure everything is working as expected and that your experience remains uninterrupted. 

Thank you for your patience and understanding throughout the troubleshooting process.  

I look forward to hearing from you soon. 

Hi @AC,

Welcome to Microsoft Q&A forum.  

Thanks for reaching out and for the detailed information you've provided. I appreciate your patience and the steps you've already taken to troubleshoot the OneNote sync problem on your iPad. 

Based on the error code you’re seeing (0xE4010643 c12qc), this issue is typically caused by an expired or invalid authentication token. OneNote’s mobile apps rely on these tokens to access notebooks stored in OneDrive for Business or SharePoint. If the token fails to refresh or the app loses track of your login state, OneNote can’t sync and throws this behavior. 

You’ve already tried the essential steps, which is great. Here are a few additional workarounds that have helped others resolve similar sync/authentication issues: 

1. Reinstall OneNote  Uninstall and reinstall the app to wipe all cached data and corrupted files. After reinstalling, sign in and monitor if syncing resumes.  
2. Check Device and App Settings 
   1. Ensure Background App Refresh is enabled for OneNote in iOS Settings. 
   2. Confirm your iPad has a stable internet connection. 
   3. Verify your device is listed as compliant in your company’s Intune/Endpoint Manager portal (if applicable). 

If the issue persists after these checks, it may stem from a deeper system-level cause. In this case, I recommend contacting the higher-level support team who can access backend details and investigate further. Once you reach out, a live agent will contact you through your preferred method and assist you step by step until your issue is fully resolved.   

You can open a support request through the Microsoft 365 Admin Center. When submitting your request, please include a brief description of the issue, along with any relevant details or patterns you've observed.  

Please understand for us that as a community moderator we do not have access to the tools or permissions required to investigate and resolve this issue in depth. That said, I’m here to support you in preparing the information needed for the support team or to assist with any other questions you may have. Please feel free to reach out anytime.   

Wishing you a great day.   

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