Directions on how to hard reset a Samsung Galaxy Prevail M820 1. Make sure the phone is turned off 2. Press and hold the up volume button (keep holding it) 3. Press the power button until it says "Samsung Prevail" while you are still holding the up volume button 4. Hold the up volume button until it comes up with "Android system recovery" 5. Using the down volume button scroll to "wipe data/factory reset" 6. Press the camera button to select it 7. Using the down volume button scroll to "Yes -- delete all user data" 8. Press the camera button (remember this erases all data and returns it to original factory settings. 9. Select "reboot system now" by pressing the camera button 10. Phone will turn off and back on.