I used to have root but not too long ago I flashed the stock tar to return to stock unrooted and when I try to update the new software it gives me an error. I tried to do the firmware upgrade and initialization thing from kies and when I entered the meid it keeps saying to reenter the information because it's invalid. I scrolled down on the phone and the serial number isn't wha came on the sticker on the back of the phone it's just 8 numbers. I checked the serial number on other phones and tablets amd they all have letters and numbers and are 11 in lenght while on the s3 it's only numbers and 8 in length. Help me please.