WARNING! Master resetting (or factory resetting) a smartphone will return it to its factory state. This means that all the personal data stored on the phone's internal storage will be deleted, such as third party apps, custom ringtones, images, downloaded content and contacts. Master resetting your smartphone will not affect data that is stored on the SD or SIM cards.

Master Resetting Through the Settings Menu:

  1. Back up the data stored on your device, if necessary
  2. From the home screen, press the "Menu" key
  3. Tap "Settings" and go to the "Accounts" tab
  4. Tap "Backup and reset"
  5. If you want, clear the check boxes next to "Automatic restore" and "Back up my data"
  6. Tap "Factory data reset" > "Reset device"
  7. In case your device is screen locked and protected by a PIN or password, enter it and tap "Continue"
  8. Tap "Delete all" to confirm

Master Resetting Using Hardware Keys:

NOTE: Use this method in case your device is freezing up, crashes and otherwise prevents you from resetting it using the settings menu.

  1. If necessary and / or possible, back up any personal data stored on the phone's internal memory
  2. With the smartphone turned off, press and hold "Volume Up", "Home" and "Power" at the same time
  3. After the device vibrates, release the "Power" button but keep pressing the other two keys
  4. After the "Android System Recovery" screen appears, you can release the "Home" and "Volume Up" buttons as well
  5. From the recovery screen, press the "Volume down" button to navigate to "wipe data / factory reset"
  6. Press "Power" to choose the highlighted option
  7. Navigate to "Delete all user data" using the "Volume down" key
  8. Press "Power" to commence the master reset
  9. Once the device has been reset, "Reboot system now" will be highlighted
  10. Press "Power" to restart your device in normal mode

See More: Samsung Galaxy S II TV: Master Resetting via the Settings Menu and Using Hardware Keys