WARNING! Master resetting your smartphone will return it to factory values, and will delete all content stored on the phone's internal storage. This includes downloaded data, photos, 3rd party apps, contacts and custom ringtones. Content stored on the SD and SIM cards will not be affected by a master reset.

Master Resetting Using the Settings Menu:

  1. If necessary, back up the data stored on your phone
  2. While on the home screen, tap "Apps"
  3. Tap "Settings"
  4. Under "Personal", tap "Backup & reset"
  5. Set the following options as you desire: "Automatic backup", "Back up now" and "App data and settings restore"
  6. Tap "Reset phone". If your device is protected by a lock screen, enter the screen unlock information
  7. If desired, mark the check boxes associated with "Erase all data" and "Erase SD card". NOTE: by marking the "Erase SD card" check box, you will also delete all the content stored on the external memory
  8. Tap "OK"
  9. Review the "Backup now" message and tap "Backup now" or "No thanks"
  10. In the "Warning" message, tap "OK" to confirm, and perform a master reset

Master Resetting Using Hardware Keys:

NOTE: use this method of reset only if you are unable to reset your device using the settings menu.

NOTE 2: Skip the first two steps if your smartphone is already shut down.

  1. With your smartphone turned on, press and hold the "Power" button
  2. Tap the "Power off" option
  3. With your handset turned off, press and hold the "Volume Down" button
  4. Press and release the "Power" button
  5. Keep holding "Volume down" until you see an image with three Androids at the bottom of the screen
  6. From the "HBOOT" menu, press "Volume down" to navigate to "Factory reset"
  7. Press the "Power" button to confirm the selection, and wait for your device to reset and reboot in normal mode


› See More: HTC One (M8): Master Resetting Through the Settings Menu or via Hardware Keys