On Windows, COM port numbers higher than 199 are not supported. If the COM port number is COM200 or higher, rename the COM port on Windows to a COM port number that is COM199 or lower. Follow these steps:
- Open the Device Manager and click Ports (COM & LPT).
- Right-click on your COM port and click Properties.
- In Properties, go to the Port Settings tab and click Advanced.
- Change the COM port number by selecting a COM port that is less than 200. Ensure it is not in the list of devices currently attached to your computer. These are listed in the Device Manager under Ports (COM & LPT).
- Click OK and accept the changes when asked if you want to continue.