Thanks for your reply.
Please check whether users set their default save locations to this drive.
Do you use shared computer activatcion for Microsoft 365?
If so, please check whether there is licensing token to roam located on this shared drive.
To get this information, you may go to
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\ClickToRun\Configuration, and check whether there is a string value of SCLCacheOverrideDirectory and whether the value to the path of the folder to save the licensing token.
Besides, as I have no environment to test for you, to help you troubleshoot this problem, it would be best to open a paid support ticket with Microsoft Support to help review your problem and help you test remotely. Paid Support Information please contact Microsoft by phone.
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