LG OPTIMUS M MS690 hard reset

(before performing a hard reset, keep in mind that all user applications and user will be deleted.
please perform back up if possible..)

1. turn off the phone.
2. press and hold these three keys: VOLUME DOWN KEY, HOME KEY,POWER KEY
3. you shall see a black screen with yellow lines, select wipe handheld, factory reset,
4. phone will turn back on and phone is back to original setting...