i tried flashing my garmin 3790 to chn ver2.2. Now my garmin boots up but the touch screen isn't working. I can't get back into usb mode to delete gupdate.rgn file because every time I plug the usb cable in. It comes up with option to change it usb mass storage mode or gps mode. But my touch screen doesn't work i can't select mass storage. I tried using garmin updater but it keep saying there's no update for my unit. any help would great. By the way I'm still new to this flashing firmware stuff.