Turn off the device.
Press and hold the Volume Up key and the Home key, then press and hold the Power key.
When the Android logo displays, release all keys (‘Installing system update’ will show for about 30 – 60 seconds, then ‘No command’ before showing the Android system recovery menu options).
Press the Volume down key several times to highlight “wipe cache partition”.
Press Power button to select.
Press the Volume down key to highlight “yes” and press the Power key to select.
When the wipe cache partition is complete, “Reboot system now” is highlighted.
Press the Power key to restart the device.