1. Before using the ADB command, you must first make sure that the computer has installed the driver of the mobile phone or tablet. You can download the driver matching the type of the mobile phone from the corresponding official website, or install the mobile phone driver through the brush wizard.

2. When the prompt "adb server expired, killing …" appears when running the "adb shell" command, you can first execute "adb nodaemon server" to view the information of the "adb server" port. As shown in the figure:

3. After obtaining the port information of ADB server, execute the command "netstat-ano | findstr" 5037, where "5037" is the port number of ADB server.

4. Find the number to the right of "TCP" from the returned result list, as shown in figure "5240". This serial number is the process number that currently occupies the "ADB server" port, and we need to stop this process.

5. Execute the command "tskill 5240" to stop the process number from occupying the "ADB server" port. As shown in the figure:

6. Finally, execute the "ADB Shell" command again, and you can enter the Shell management operation mode normally.