Also download LG Flash Tool and unzip, you should find two files, a Setup EXE file and a DLL file.
Run the Setup EXE file by double-clicking on it and install LG Flashtool.
Once done installing LG Flashtool program, uncheck “Run LGFlashTool” and click on “Finish”.
Step 4. Next, copy and paste MegaLock.dll file to C:\LG\LGFlashTool directory.
Step 5. Open up Device Manager on your Windows computer. (Go to Control Panel->Hardware and Sound->Device Manager)
You should see under Ports (COM & LPT), “LGE Mobile USB Serial Port”. If you don’t see it, you don’t have LG Drivers installed.
Download and install LG Drivers and come back to Step 5.
Double-click on “LGE Mobile USB Serial Port” if you don’t see COM41.
Step 6. Go to Port Settings->Advanced.
Then set your COM Port Number to COM41 and click on “OK”. LG Flashtool software will not work unless you do this that is why we are doing this.
Step 7. Open up LG Flashtool software, you should see a window like below:
This is where we will set the DLL file and stock firmware.
Check “Select Manual Mode” ON, then set the DLL to the DLL file you downloaded earlier. And also set S/W to the stock firmware .tot file you unzipped earlier. And hit “OK”.
Step 8. Click on the Right Arrow button at top left of LG Flashtool software.