How to save information that I add in private class notebook in Microsoft team

Hi wanitcha limsoontaragul, 

Welcome to the Q&A Community 

I’m here to assist your problem. 

Could you please provide more information to me for a better support:   

• You are using Business account or Personal Account?   
• You are using OneNote Desktop App or OneNote Web App ?  
• Can you tell me more about the exact error message you see shown on your screenshot? 

I'll outline how to properly add sections/pages to a private Class Notebook (which typically refers to the student-specific private sections in a Class Notebook), followed by troubleshooting steps to resolve the saving/sync and "out of space" errors. 

How to add sections or pages in a Private class Notebook: 

In Teams, Class Notebooks have structured areas: Collaboration Space (group editable), Content Library (teacher shares read-only), and private student sections (visible only to the student and teacher). To add to private areas: 

1. Open your OneNote, then select the Class Notebook tab. 
2. In the Class Notebook interface, click the Class Notebook ribbon/tab at the top (if not visible, ensure the add-in is loaded). 
3. Select Manage Notebooks. 

Under "Student notebook sections," click + Add section, enter a name, and save. This adds the section to all students' private areas.  

You can give student permission to view and edit these sections by click “Collaboration Space Permissions”. 

To add a page: Navigate to the new section, then click + Add page at the bottom of the page list. Enter content and it should auto-save. 

If adding directly in Teams fails, switch to the full OneNote app: 

• In Teams' Class Notebook tab, click the ellipsis (...) > Open in Desktop App (or Open in Browser for web version). 
• Make changes there, then force a sync (right-click the notebook name > Sync This Notebook). 

Changes should save automatically in OneNote, but if not, manually sync via File > View Sync Status > Sync Now. 

Even if your Microsoft 365/OneDrive storage is unused, the error often points to local device space (OneNote caches data on your hard drive) or sync problems. Here's a step-by-step guide to fix it: 

Check and free up local disk space: 

• OneNote stores temporary cache files on your device's main drive (e.g., C: on Windows). If it's low on space, you can't add/save content. 
• On Windows: Open File Explorer > This PC > Right-click your main drive (usually C:) > Properties. Check available space—if under 5-10 GB, free up room by deleting temp files (search for "Disk Cleanup" in Start menu) or uninstalling unused apps. 

Clear OneNote cache specifically:  

• Close OneNote/Teams. 
• On Windows: Navigate to %AppData%\Microsoft\OneNote (paste in File Explorer address bar) and delete contents of the cache folder (it'll rebuild). 
• Restart OneNote/Teams and try adding again. 

Though you mentioned available storage, large attachments or versions can fill quotas quickly. 

• Close unused notebooks: In OneNote, right-click > Close This Notebook (removes local cache after syncing). 
• Disable auto-sync of attachments: In OneNote > File > Options > Sync > Uncheck "Download all files and images." 
• Delete old versions: In OneNote > History > Notebook Recycle Bin > Empty Recycle Bin. 
• Check overall storage: Go to onedrive.com > Settings > Options > Storage (or in Teams admin if it's a school account). 
• Repair Office: Search for "Apps & features" in Windows > Find Microsoft 365 > Modify > Quick Repair. 
• If still broken, download/reinstall the add-in from Microsoft (run as admin). 
• For school accounts, contact your IT admin; permissions or quotas might be restricted. 

Noted**:** Education accounts using OneDrive are experiencing a sync bug, even though the OneDrive storage space is not yet full (as you mentioned above). Many other users are experiencing the same issue as you, and we've already reported it to the Microsoft development team so that a fix can be made as soon as possible.

As the forum moderator, we are also waiting for official information from Microsoft regarding this OneDrive malfunction.

I am sincerely sorry that this issue may interfere with your use of the service.

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