LG G3 User Manual page 150

Important notice
5. Using the Hard Reset (Factory Reset)
If your phone does not restore to its original condition, use a Hard Reset (Factory Reset)
to initialize it.
1 Turn the phone off.
2 Press and hold the Power/Lock key + Volume Down key on the back of the
phone.
3 Release the Power/Lock Key only when the LG logo is displayed, then immediately
press and hold the Power/Lock Key again.
4
Release all keys when the Factory Data reset screen is displayed.
5 Press the Volume Keys to highlight Yes, then press the Power/Lock Key to
continue.
6 Press the Volume Keys to highlight Yes, then press the Power/Lock Key once
more to confirm.
7
Your device will perform a factory reset.
WARNING
If you perform a Hard Reset, all user applications, user data and DRM
licenses will be deleted. Please remember to backup any important data
before performing a Hard Reset.
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