Reset, hold both home and power buttons until the iPhone begins to start, usually takes about 10 seconds of holding both buttons. If still nothing try Reset while on Wall Charger, this can take about 20 seconds of holding both buttons while on Charger. If still nothing and you decide to Restore you iPhone with iTunes on computer, you may need to use DFU Mode Restore. Here are steps: Open iTunes on computer. Connect iPhone to computer with USB cable. Hold both Home and Power button, after exactly 10 seconds release the Power Button, keep holding the Home button until iTunes recognizes iPhone in Recovery Mode, usually about 20 seconds time. If the iPhone screen is black, blank this is DFU Mode. Click the Restore button of iTunes. DFU Mode can be difficult to enter sometimes, just keep trying. DFU Mode is a black, blank screen with iTunes saying Recovery Mode.