Port 8080 is already in use express code example
Example 1: npm port already in use
$ lsof -i tcp:3000
$ kill -9 PID
Example 2: stop npm running on port 3000
netstat -ano | findstr :3000
taskkill /F /PID PID_of_port
$ lsof -i tcp:3000
$ kill -9 PID
netstat -ano | findstr :3000
taskkill /F /PID PID_of_port