[AT&T SGH-i337] Need help flashing stock rom (complete noob)
Hello people, before I begin I'd like to say I'm a fool so forgive me if I have trouble answering any questions that may seem trivial to you phone guys.
Anyway, a while back I rooted my device through some neat website with a lambda symbol, and was enjoying the pleasantries of root access. Well one day I turn on my phone and am greeted with "System software not authorized by AT&T has been found on your phone". I would prefer to just revert back to stock and not bother with rooting again.
As a side note, I was on kitkat 4.4.2
Now, from my preliminary research I've gathered I'll need some samsung usb drivers, Odin, and the stock rom for my device (at&t sgh-i337).
From what I can tell, I downloaded/installed the correct drivers
I downloaded Odin v3.07
The stock rom I am downloading is "I337UCUAMDL_I337ATTAMDL_ATT.zip" I am also downloading "I337UCUFNB1_Rootable_Full_Odin.rar".
Is this all I will need?
While the roms were downloading, I tried to connect my phone to Odin (in download mode, running Odin as admin) yet I didn't see anything like COM:6. Would this mean a mistake in the drivers I downloaded?
I'm a noobie at all of this, so before I mess my phone up even more, does this sound correct? I'll try to answer any questions people have. I hope I haven't somehow doomed this phone
Any help would be greatly appreciated, thanks