Dear @Andrew Kwok,
Good day! Thank you for posting your question in the Microsoft Q&A forum.
We apologize for any inconvenience you may encounter when using our services/ products. Based on your description, kindly try these following steps:
Use the Assignments Tab to Trigger Notebook Setup
- Go to the affected Class Team.
- Click the Assignments tab.
- Create a new assignment.
- In the assignment window, click Attach > Class Notebook.
- Close the assignment window.
- Return to the Class Notebook tab and try setting it up again.
Temporarily use the Web Version of Teams
- Visit Microsoft Teams.
- Sign in and navigate to your Class Team.
- Try accessing the notebook from there.
Clear the Teams client cache
Classic Team
- Go to Windows + R.
- Enter %appdata%\Microsoft\Teams > OK.
- Delete all files and folders in the directory.
- Restart Teams.
New Team
Method 1: Reset the App
- Select Settings > Apps
- Under the app > installed apps, select Microsoft Teams.
- More options button (...) Reset > Advanced Options on the right
- Restart Teams.
Method 2: Delete Files
- Go to Windows + R.
- Enter %userprofile%\appdata\local\Packages\MSTeams_8wekyb3d8bbwe\LocalCache\Microsoft\MSTeams > Verify.
- Delete all files and folders in the directory.
- Restart Teams.
Here is a reference: Clear the Teams client cache - Microsoft Teams | Microsoft Learn
Update or Reinstall Teams
- Ensure you're using the latest version of Teams.
- If needed, uninstall and reinstall the app.
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