HTC Desire 820s dual sim User Manual page 53

53 Backup and reset
3. Tap Factory data reset.
4. Tap Reset phone, and then tap Erase everything.
Performing a factory reset using hardware buttons
If you can't turn HTC Desire 820s dual sim on or access settings, you can still perform
a factory reset by using the hardware buttons on HTC Desire 820s dual sim.
1. Press and hold the VOLUME DOWN button, and then press and hold the
POWER button.
2. Wait for the screen with the Android image to appear, and then release the
VOLUME DOWN and POWER buttons.
3. Press the POWER button to go to the Android system recovery screen.
4. Press VOLUME DOWN to select wipe data/factory reset, and then press the
VOLUME UP button.
5. Press VOLUME DOWN to select Yes--delete all user data, and then press the
VOLUME UP button. A message appears when the data has been wiped.
6. To restart the phone, select reboot system now, and then press the VOLUME
UP button.