[Samsung Galaxy S7 Edge Questions and Answers] S7NOOB:
Hey Everyone,

I've been reading up on the forums but I'm willing to admit I now need more direct help.

I have a Samsung Galaxy S7 andI wanted to downgrade the OS back to Nougat from Oreo so I could spoof on Pokemon go. I move all the files I'm interested in keeping to a new handset (so the handset being worked on is not my primary one, it's expendable, so I didn't bother backing up).

I started trying to learn to flash an older OS. I quickly came across TWRP and Odin. I tried several times to flash with Odin, but I gather that Odin doesn't allow downgrades, and I couldn't find an OS in the correct format anyway. I discovered that to downgrade you have to use TWRP. So I use odin to install TWRP and learn to use it (on a basic level)...

I found a stock OS post on this forum and downloaded it, and tried to flash it with TWRP as directed by the poster. Well that didn't work, it went through the flashing process, errored and then turned itself off, tried to turn itself back on and hangs at the samsung logo. It seems I managed to completely wipe the OS off my phone. Luckily it still talks to the computer so I stick TWRP back on it to try to flash an OS. I can't find a TWRP friendly file (has to be a zip file??). When I try with Odin to flash stock ROM from Sammobile it fails, here's the log contents:

<ID:0/005> Odin engine v(ID:3.1301)..

<ID:0/005> File analysis..

<ID:0/005> Total Binary size: 4203 M

<ID:0/005> SetupConnection..

<ID:0/005> Initialzation..

<ID:0/005> Set PIT file..

<ID:0/005> DO NOT TURN OFF TARGET!!

<ID:0/005> Get PIT for mapping..

<ID:0/005> Firmware update start..

<ID:0/005> NAND Write Start!!

<ID:0/005> SingleDownload.

<ID:0/005> sboot.bin

<ID:0/005> FAIL!

<ID:0/005>

<ID:0/005> Complete(Write) operation failed.

<OSM> All threads completed. (succeed 0 / failed 1)

When it goes through this failure, this is what the phone screen says on download mode.

ODIN MODE

DOWNLOAD SPEED: FAST

PRODUCT NAME: SM-G930F

CURRENT BINARY: Custom

SYSTEM STATUS: Custom

FAP LOCK: OFF

Secure Download : Enabled

WARRANTY VOID: 1 (0x030c)

RP SWREV: B:3 K:1 S:2

SW REV. CHECK FAIL (BOOTLOADER) DEVICE: 3, BINARY:1

I'm pretty sure this means I'm trying to use the wrong image, but I can't find one that works.

I've tried looking for images I can flash in TWRP, and I found something online called Lineage, download that, and HAHAHA it works!! phone is alive again, but I can't install any aps. They say they are installed but they aren't visible anywhere.

I've tried several different stock OSes with Odin, but I always get the same error.

I think hey, maybe I downloaded the wrong version of the OS from Sammobile, so I try to check my IMEI number in the "about phone" section but it's blank! I've somehow deleted the IMEI. I do still have the box though (thank god) so the IMEI number is 359468 07 8490758. According to google you can use the 7th and 8th digits of the number to get the country of origin to make sure you're using the right image, however, My IMEI number 7th and 8th digits are 07, but according to multiple sources, the 07 source doesn't exist!!!

So several possible questions that I just can't work out in this whole situation.

-What the hell is my country of origin, and how do I find the OS that should work for this phone (UK unlocked) considering I have no idea of my country of origin??

-Is this error actually caused by an OS mismatch?

-If it's not, what the hell do I do now? I am at a total loss.

-Is there a stock nougat version I can flash with TWRP? because I'm pretty sure I know how to do that, whereas I can barely get Odin to do anything for me.

Other random bits of info that may be relevant:

It's Exynos, I had to look that up in the initial research stages

I've checked and re-installed the samsung drivers about 3 times at this point

I tried something called x3z samsung tools to try to repair the IMEI, but it just says "card not found" and won't open. Guessing that's something to do with the fact that the IMEI number is blank?