Most guides are utterly crap.
I'm away from my PC but find and download the newflasher program. That when run, will give you the option to extract drivers, do it, the right click on the inf file and install it. Now copy the new flasher program in to a folder with your new firmware in, make sure you downloaded the correct one.
Then turn off your phone, all the way. Hold down the vol down button and plug a usb cable to connect to your pc, give it a moment, nothing will happen on the screen, it will remain blank.
Now run the newflasher program again, forget the drivers as you have done that and let it do its thing.
Done.... Well it will be after about 10 Min, on your computer screen it will show you progress.
If no one has replied with links to the programs I'll do it but it's going to be a few days, I'm currently sailing across the ocean and my signal is about to vanish
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