Originally Posted by jraulj
mine did the same via usb... my cable was bad, but the pc saw the crius.
i think there's something similar going on with yours.
you have connection via 3DR (com 21 is your 3DR right?)
but the protocol is missing somtehing...
remove the 3dr power down your quad and close the planner.
connect all again, start planner and try again without clicking the connect button in the top right corner. (only select the appropriate comport)