I dont know what is wrong with my phone. I have looked everywhere, i have seen similar problems but they are not the same. Situation: I don't have network on my phone, its disabled somehow. Can't access networks from the Settings, Chrome crashes, Google Play Store wont come open.. I dont know. Lots of things try to open but then crash and close. I figuered I need to go back to stock firmware. OK. Downloaded LG Flash Tool 2014. I need to get to the download mode yes? - Tryed to get there, gave me error: "secure booting error - boot certification verify" and that's it?! I can't do anything. Is here someone who can help me. What I need to download, which kdz or dll fail I need, I really don't know their difference.. HALP!