The Windows port is occupied by the process but the process is closed

The Windows port is occupied by the process but the process is turned off before this program is opened, prompting for a failure or the port being occupied.

This is because the process uses a similar statement such as System ("Start A.exe"), or when the process is closed using a *.bat

The batch file (called cmd) closes the process. Cause the other processes have not exited yet,

Neither the Windows CMD process nor the conhost process will completely exit. At this point, if the parent process to start start exits,

Will not quit very clean. The port is left behind.

Solution:
Just use Task Manager to kill all the see CMD process, there must be one or several of the dirty process left behind. Conhost will quit after he kills.
Then you'll find the port or whatever is released. Pro-Test effective ... Although Conhost did not quit