Mission Planner Doesn't Connect to Pixhawk Cube

I connected pixhawk cube, battery, gps, and computer. But when i try to connect mission planner to pixhawk, i get error. Can you say why?

Often a driver issue.

Also make sure in Mission planner you have the correct baud rate. On USB it should be 115200.

And from personal experience yesterday, don’t assume the cable is any good. I threw out 3 “perfectly good” usb cables yesterday because they were not in fact “perfectly good”.