Poate numai un hard reset :
http://www.hard-reset.com/lg-optimus-l9-p760-hard-reset.html
dar pierzi aplicatii/jocuri/fisiere.Scoate microSD-ul!
Mai poti incerca cu LG PC Suite:
http://www.lg.com/ro/suport/pc-suite
http://lg-pc-suite.en.softonic.com/