Clearing the registry: COM port is occupied
1、Start menu, open Run(Shortcut key: Start button+R)
2. Inputregedit, confirm

3. Expand sequentiallyHKEY_LOCAL_MACHINESYSTEM CurrentControlSetContorl
COM Name ArbiterDelete ComDB and restart the computer
Or open Edit - Find

inputComDBClick to find the next one

Then delete ComDB and restart the computer