After LGN4 enters the Recovery mode, a red exclamation point is displayed.

Maybe you are forced to have to root your phone, maybe you are a hard-pressed programmer like me, and root the device for debugging bugs. For whatever reason, after the root operation is complete, open the system to stay on the X interface, or google's pop-up window. After entering the Recovery mode, the robot is down, and a red exclamation mark is displayed on the chest ..., table panic, the table secretly scolded more than ten times the magic horse brush genie, one-click root and other pitfalls ....., in fact, I suddenly felt a little flustered...

Http://www.lg.com/us/support/product-help/doc-1363039396376-en-LGEAI this instruction will help you answer the question, according to this should be no problem, I am so solved.

If the above connection cannot be opened, refer to the following:

Factory Reset using physical buttons

1.	Power off your phone.

2.	Press and holdVolume Down, And then pressPower buttonUntil the device turns on (while still pressing Volume Down). You will see the word Start with an arrow drawn around it.

3.	PressVolume DownTwice to designate Recovery mode.

4.	PressPower buttonTo restart into Recovery mode. You will see an image of an Android robot with a red exclamation mark.

5.	While holding downPower button, Press and releaseVolume Up.

6.	Use the volume keys to scrollWipe data/factory resetAnd pressPower buttonTo select it.

7.	Scroll downYes-erase all user dataAnd pressPower buttonTo select it. Your device will reset to factory settings.

Note:

If at any point during the above steps your phone becomes unresponsive, you can restart it by holding downPower buttonFor several seconds.