Unresolvable "Sync Error" for OneNote, ~500GB free

Dear @Chlöe,

Thank you for reaching out and for providing detailed information about the issue. I understand how disruptive it can be when OneNote stops syncing across your devices, especially when you rely on it for your notes.

According to its description, the reason for this issue is that Microsoft 365 Education now uses a shared storage model for the entire school, rather than unlimited or large individual quotas.

• Shared storage pools: Instead of unlimited or oversized OneDrive space for each student, Microsoft offers a shared storage pool (a combination of OneDrive + SharePoint + Exchange) for the entire school. For example, a school allocates a total of 100 TB of storage to the entire tenant, and each authorized user (A3/A5) adds an extra-GB to the pool.
• Everyone is affected when the school's storage pool is full: If the tenant's storage pool reaches 100% capacity, Microsoft sets the environment to read-only mode. This prevents everyone from uploading and sharing data, even if your personal OneDrive screen has plenty of space.
• For more information: Changes to storage offerings across Microsoft 365 Education

Therefore, the problem is not with the individual accounts of the students, but with the school's overall storage limit. Your tenant's shared storage capacity may have reached or be close to the limit, so Microsoft prevents everyone from sharing and saving data.

Since you're using an education account, I recommend contacting your IT administrator directly. They may be aware of ongoing outages or account-specific issues. It can:

• View your tenant's overall storage usage in the Microsoft 365 admin center.
• Free up space by removing old or inactive accounts, emptying the trash, or adjusting retention policies.
• Purchase additional storage or upgrade licenses if needed.
• If your tenant is locked, request a temporary extension from Microsoft.

Please understand that as a forum moderator, I do not have access to the administrative systems to effectively troubleshoot this issue due to privacy and security restrictions.

I hope this information has been helpful. Please feel free to reply below if you have any update or further concern.  

Your understanding and co-operation are highly appreciated. I am looking forward to your response!

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