Hi Noxxienox,
Thanks for your post in Microsoft Community.
I understand that you are encountering the problem that other whiteboards are lost when the Microsoft Whiteboard returns to the home page.
I noticed that you have reinstalled multiple times, but nothing seems to help. When you reinstall the whiteboards show up again indicating that they are there, not missing.
I suggest you try another network. If there is a problem with the network, it may cause the whiteboard content to fail to load.
If the whiteboard does not work after changing the network or reinstalling it, you can log in to the web terminal and use the web terminal to operate temporarily, which can be used as a temporary solution.
Please feel free to let me know how it goes.
Kirk | Microsoft Community Support Specialist
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