Yes I have had the exact same problem pop up for the first time today. "Error Unknown" Popped battery out and back in again and everything was fine. Still makes me a bit nervous.I have had plenty of barometer error messages on 1.9 which prevented the craft from starting, now on 1.3 the error has changed to " unknown error 42 please contact dji" all I have ever had to do was whip the battery out and then back in again and it starts. Anyone else had this sort of problem.