The 3.5mm plug must be pushed completely into the radio port. Sometimes plastic radio housings or dust covers prevent the jack from seating deeply enough to make electrical contact.
Once the data is uploaded to the computer, make your changes. vertex vx351 programming software work
Turn the radio off, plug the cable firmly into both the PC and the radio, and then turn the radio volume knob clockwise to power it on. vertex vx351 programming software work