Answered: how to unlock lg ms870

1. Turn the power off.
2. Press and hold the Power/Lock Key together with Volume Down Key .
3. Release the power key for 1 second and hold it again 
4. Release both keys when the FACTORY RESET screen is displayed.
5. Press the Power/Lock Key to continue or the Volume Keys to cancel.
6. Press the Power/Lock Key once more to confirm or the Volume Keys to cancel

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