The error "Could not open serial port", means that you do not have the correct comm port selected in Projects. Go to "Options" -> "Project Options" -> on the Communications Tab, choose the correct "Serial Port" under "Serial Options".
How do I fix failed to open COM port?
- Make sure that you have the necessary drivers. ...
- Verify that the port isn't open/disconnect the cable. ...
- Stop the Windows Fax and Scan service. ...
- Disable the serial port in Device Manager. ...
- Try using a different cable. ...
- Restart the device. ...
- Reinstall the serial port driver. ...
- Make sure that the system is up to date.
What is Open port error?
When printing from a computer and using a serial port, if you get the "Failed to Open Serial Port" error, that usually means that you have two or more serial printers or devices (Palm Pilot, modem, printer, etc.) installed, both using the same COM port.
