From the home screen, tap the Menu icon. Note: Learn about the importance of adding a password on your device to protect your privacy as well as how to report a lost or stolen phone:Â www.att.com/stolenphone.
Tap the Settings icon.
Tap Device.
Scroll down, then tap Security.
Tap Phone Lock.
Tap the desired option. Note: For this demonstration, 'Lock Phone Now' is selected.
Enter the required security code, then tap OK. Note: The default security code is '0000.'