Our terrier likes to "help" my wife whenever she browses the web with her Acer C7 Chromebook. Last night, she helped by walking on the keyboard, which now does not respond to any key being pressed. I've reset the Chromebook back to its factory default configuration. No joy. It does respond to an external keyboard plugged into the USB port. I can't find any key that is obviously stuck. The machine is fairly new and in otherwise pristine shape. Does anyone have any suggestions?