With your device powered off, press and hold down the Power button, Home button, and Volume upbutton until you see ‘Recovery booting’ at the top of the screen and the Galaxy S4 logo.
When Android System Recovery screen appears, press the Volume down key to scroll down until ‘wipe data/factory reset’ is highlighted.
Press the Power button to select.
Press the Volume down button to scroll down until ‘Yes – delete all user data’ is highlighted.
Press the Power button to begin the reset process.
When the Android System Recovery screen displays again, ensure that ‘reboot system now’ is highlighted, then press the Power button.
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