@watson Hello Watson, I did all you asked and it still doesn't work.[image: 1537997576707-screen-shot-2018-09-26-at-5.20.59-pm.png]. The COM port is open and selected. When I try the hello world sketch I get the following error: A fatal error occurred: Invalid head of packet ('5') A fatal error occurred: Invalid head of packet ('5') Thanks for any help.