[AT&T Samsung Galaxy S 4 Q&A, Help & Troubleshootin] Aelyus:
So I have a problem guys, I'm going to tell you all the long story, I just recently bought a S4 from Telcel in México, LTE edition, the model is SGH-I337M, and came with build I337MUMUAMG1, 4.2.2.

I was anxious to tinker with it, so first thing I did as soon as I came home was rooting it with CF-Auto-Root, everything until that point was smooth sailing, but I couldn't make the I337M version of Philz Touch Recovery to flash via Odin, so I flashed the GT-i9505 version and IT WORKED, it booted to recovery normally, rebooted to system, etc. So I thought "oh boy, I'm ready to go". But before that, I read that for data & Wi-Fi to work properly in 4.3 Custom Roms I had to flash the 4.3 modem.bin file via Odin, so I did that. No OTA, no 4.3 Stock Rom, only the modem-bin file. The modem version never changed in the "About Device" tab to "I337MVLUEMK6" like it was supposed to do, it stayed as "I337MUMAMB2" but I also read that was normal so I didn't think about it much.

After that I went into recovery with my ready-to-flash files in my SD, wipe my system/data/cache/etc without making a Backup because that's how retarded I am and try to flash my ROM only to get it aborted every time due to "assert failed: getprop("ro.product.device") == "jfltecan" ||" issues, so I assumed it had to do with me using the GT-i9505 version of Philz Touch with a I337M Canadian Custom ROM. I shat bricks for a while because I had wiped my system and I had no backup, so I just turned my phone off, downloaded the "I337MUMUAMG1" Telcel Stock Rom, turned on my phone in Download Mode and flashed it via Odin while I prayed.

It worked, it booted, everything was alright with the world again (but not so much on my pants where tons of bricks were shat), I had voided my warranty but whatever, I was gonna Root and Triangle Away that thing to make my phone fully stock again, so I get ready to do exactly that, get my phone into Download Mode, and Root it with CF-Auto-Root, again, it worked, it booted, and had the SuperSU icon, smooth sailing again, OR SO I THOUGHT.

I open SuperSU to update dem binaries and a pop-up emerges saying that Samsung Knox had been detected and if I want to attempt to disable it. Oh boy, I was not ready for this, I hadn't recovered from the last shatbricking session, and now my pants were a national disaster area. Anyway, I also read that using Triangle Away with a Knox enabled phone was a highway to a very expensive paperweight, so thankfully I was smart enough to don't try it.

As I kept shatting bricks I decide to reflash the Stock "I337MUMUAMG1" Telcel Rom via Odin to keep my phone as safe and near stock as possible, everything worked, and now I'm running the "I337MUMUAMG1" build, with no root, stock, with yellow triangle and apparently, Knox. :crying:

I got curious about it, so I went into Download Mode to search for the Knox Warranty Void Flag... But I didn't got it, neither the Warranty Bit. On Download Mode I get only the Usual:

ODIN MODE

PRODUCT NAME: SGH-I337M

CURRENT BINARY: SAMSUNG OFFICIAL

SYSTEM STATUS: OFFICIAL

USB-CONFIG-LSB: 0x30

WRITE PROTECTION: Enable

And I don't have any Knox apps on my drawer, but they appear on the "Application Manager -> All" menu, so I'm confused as hell, and since I can't check my Bootloader version I can't know if I have Knox on my bootloader or only on my Rom. And I'm way to scared to try anything, and also scared about OTAs and updates since I don't know the state of my phone. Any help on this?

tl;dr: Got brand new SGH-I337M with I337MUMUAMG1 as Stock. Rooted, Flashed Philz Touch for GT-i9505, Flashed 4.3 modem.bin only, Tried to flash Custom Rom, messed up, Flashed Stock I337MUMUAMG1 again, Rooted, got Knox popup upon opening SuperSU for the first time, shat bricks, Flashed Stock I337MUMUAMG1 again to be as stock as posible. If I boot into download mode I don't get Knox Warranty Void Flag in the Download Mode, don't have Knox apps on my App Drawer but I see them on the Application Manager -> All. Too scared to try anything until I know if I have Knox enabled on my Bootloader or only Knox Apps on my Rom.

Any help with this will be greatly appreciated, many thanks in advance, and thanks for reading.

EDIT: FORGOT ABOUT SOMETHING. After Flashing Stock I337MUMUAMG1 For the second time after getting the Knox warning popup on SuperSU, I got an OTA, couldn't cancel it but I don't know if it changed anything, since my build number was it was I337MUMUAMG1 still, it was a 250mb file.