Hi @ 徐文青(Wenqing),
Based on your warning message that you cannot connect to the Microsoft Exchange Information Store service, restart the service when you run the get-mailboxdatabase command?
In my tests, when I stopped this service, I also failed to get the mount information with the same warning:
Please refer to the following steps to check if this service is running:
1. Open Control Panel and select Large Icons
2. Click the Administrative Tools and select services
3. Open the services and select the Microsoft Exchange Information Store
4. Check if it is running
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