The red core error statement is: [node mon] app crashes-wait for file changes before starting. ...

Combined with the above sentence "Failed to start the checker on 127.0.0. 1: 9229: the address is ready and in use", we can know that the 9229 port has been occupied by a program, and the corresponding program needs to be killed before the project can continue to start.

So now it becomes how to find the program that occupies the specified port and kill it.

1. Start-> Run -> Cmd, or press window+R to bring up the command window.

2. Enter the command: netstat -aon | findstr "9229 "to query the operation of the degraded port.

Remember the number in the last column, here is "10208", and this number is the PID corresponding to the occupied port "9229".

3. Continue to enter the command: tasklist | findstr "10208" to see which process or program occupies port 9229, and the result is obvious: chrom.exe.

4. Open the task manager, switch to the process tab, check who the process corresponding to 10208 is in the PID column, and then click to end the process.

5. If you can't see the "PID" column, you can click "Select Column" in "View" and then check the corresponding column on it.