This article will help answer this commonly asked question
In LinkManager you can predefine the COM port used for serial communication.
- Right-click the tray icon (might be hidden, click the ^ symbol in the Windows system tray).
- Select "Options"
- And type in the com port number you wish to assign to the serial port emulator (com0com)
If you experience issues changing the COM port you can try a reboot of the PC – the only guaranteed solution to release a COM port in Windows. You can always monitor the actual COM port setting by searching for the “com0com” device in the Windows Device Manager.