LOL. My E71 did this when I first got it, do you have auto keypad lock on? If so, unlock other Nokia phones, when you press a button, it doesn't light up the screen and tell you to unlock the phone because it has that feature where you hold down the d-pad and it shows you the time and date. For about an hour I thought my phone was defective. Press the left softkey then function key and see if everything lights up again.