[Sprint  Galaxy Note 4 Q&A, Help & Troubleshooting] Coyote76:
Hi guys, I've found this guide.

But I don't understand if can work. I have a N910F and I can test.

Someone can do the Rom ?

Sorry if I'm OT

This is the guide:

"Q] KNOX Warranty void hacked. Don't loose warranty anymore.

Hi Guys. Hope here are some programmers.

I have a good news for all Galaxy Note 4 users and owners, who have ever rooted it and got "KNOX WARRANTY VOID: 1" message. So from now(if developers, who write cf-auto-root tool) will use my advice, you can forget about warranty void. I'm linux expert and C/C++ programming expert too. So, once Samsung told me, that because of root warranty is void and they don't wanna repair factory cauzed mainboard damage(short-circle on mainboard), I wondered, how to solve that problem. And I found the solution(will do it on my own for my device when it gets back from service center) to hack that warranty void thing. So, first of all you go there sammobile.com /firmwares/database/SM-N910C/ to get original firmware(in my case SM-N910C, but choose yours, or you'll kill your device). You'll get original firmware. And KNOX uses value to print if warranty is 0 or 1 (0x0 or 0x1). But actually it makes no sence, since in service centers they just place Odin boot to check if it's 0 or 1. More over, they not goig to place root on it, to figure out, if knox works fine or not.

WARNING!!! READ CAREFULLY!!!

Any kind of warranty or usability are voided! By using this hacking method you accept, that you USE IT ON YOUR OWN RISK!!! This info basically is meant for xda-developers crew to release a massive hack. Any broken, died etc phone - IS YOUR OWN FAULT! If you don't know what you're doing - DON'T USE IT, UNTILL YOU KNOW WHAT YOU'RE DOING!!!

So guide to disable KNOX WARRANTY void:

1) download original firmware

2) unzip file you get(it is about 1.6 GB).

3) Need to modify sboot.bin image. Suitable is disassembler, or hex editor like Octeta for linux.

4) Search "KNOX WARRANTY VOID" text in sboot.bin file. You'll find something like (test device) ??? KNOX WARRANTY VOID: %d. In my case start position is 2786.

5) Now need to make it print Zerro (0). They use ordinary printf() command. "%d" symbol means, that digital value(number) gonna be printed. Here we can place statical Zerro, or if you're good at assembler and hacking, can search what varriable is used and where it comes from. But regular 0 on Odin near field of "KNOW Warranty void" is enough. So we take "%d" down and placing 0 instead.

6) When sboot.bin hacking is done, upload new firmware and reboot device.

7) Place reset to factory firmware on emergency recovery during boot(so that root will be lost).

8) Done. Run Odin, and see that Odin shows Warranty void 0. Now warranty restored and you can go to nearest repair center, and make them note, that warranty void is 0. If they update firmware and it's 1 again, it's not your problem anymore.

Hope XDA-DEVELOPERS crew will release new cf-auto-root with this hack, or make a firmware(factory default) with KNOX warranty void hacked.

To those, who are not a programmers, please ask xda-developers to apply that stuff to firmware on this site.

Now the question, can we cooperate with xda-developers to make that hack publicly available?"