Important note

This only works if your Switch hasn't ever been online. If it was, you might already be banned for whatever reason OR Nintendo has some kind of a "log snapshot" that will be different from the one that will be created once you go online again with your Switch at the end of this tutorial (leading to a ban).
The only use case for this is, if you have a Switch, that never went online (!) and you started using CFW/NSPs/Homebrew WITHOUT creating a clean NAND dump BEFORE.

I had a friend that never went online but also never created a NAND dump and started using all the custom firmware niceness as it came out. Now that it's easy to create an emuNAND for that, he wanted to go online with his sysNAND. @shchmue helped me out on Discord cleaning up his NAND to remove all logs and afterwards he indeed was able to play online (and still is).

Obviously I'm not responsible for any bricks or other bad and explosives things happening to you following this.
Also I can't guarantee it will work as intended and/or you won't be banned. There's a thousand reasons the latter could happen (or already happened for whatever reason). However this guide is the only way for this specific use case and should work.

Steps

Since this involves using memloader and HacDiskMount to mount your NAND (aka eMMC) in Windows, I'll save myself a lot of time by pointing you to Raj's fantastic guide (because why writing everything down another time?) so let's get started:

1. Use hekate (faster and probably better than SX OS) to create a NAND backup (aka eMMC dump). Dump both, Boot0/1 and the full raw NAND.
   Seriously this is like the most important step ever! If anything goes wrong or you accidentally delete one more thing than you should, restoring your NAND backup only takes around 15 - 20 minutes in hekate and lets you start over.
   1. Optional: Create an emuNAND/emuMMC out of your current "hacky" sysNAND to continue using CFW there after your sysNAND is clean.
2. If you haven't ever used your Switch in combination with your computer you need to install the USB drivers first. You can follow the first step of this guide to do so.
3. Follow this guide by Rajkosto to the point where you are able to mount your NAND in Windows.
4. Mount the USER partition and delete everything on it. Unmount it afterwards.
5. Mount the SYSTEM partition and delete everything on it except these two things:
   
   • content (folder)
   • 8000000000000120 (file that is inside the save folder)
   
   Unmount if afterwards.

That's it! You should end up with only two folders and nothing else on your SYSTEM partition: content and save.
And inside that save folder you deleted everything except that single file I mentioned above (8000000000000120).

Credits

@shchmue for telling me exactly what to do
@rajkosto for his HacDiskMount guide and all his fantastic tools
@CTCaer for his work on hekate (dumping/restoring NAND is so fast and easy nowadays)
@m4xw for making my life complete with his libnx RetroArch port (actually not related to this guide but had to mention it)

 

[Hayato213]

burnt fuses in Hekate says 7/6 ??

What # and firmware it give you?

 

[Quattro74]

Ha Ha. At least I can go online with certain games. using LAN Play..

 

[SylverReZ]

Ha Ha. At least I can go online with certain games. using LAN Play..

Going online with a modded Switch is an instant ban.

 

[Quattro74]

Well, I think I banned myself by not using an emunand. I can still use this online using un-official Lan Play.

 

[SylverReZ]

Well, I think I banned myself by not using an emunand.

That's true. You should've thought about it first before hand. And it's not like you can recover your NAND back to the way it was, as the ban is tied to the console's ID.

 

[binkinator]

https://switchbrew.org/wiki/Fuses#Anti-downgrade

 

[SylverReZ]

https://switchbrew.org/wiki/Fuses#Anti-downgrade

Thanks for the info.

 

[Quattro74]

Indeed, thanks for this info on Fuses.

 

[binkinator]

Indeed, thanks for this info on Fuses.

Booting via Hekate will make sure your fuses remain unburnt (and irrelevant to your boot process.) As @Hayato213 and @M4x1mumReZ have stated you’re probably already hosed and there’s not much you can do but lock your system down and try to sin no more. Any changes you attempt to do (like downgrades or log deletion, what-have-you) at this point will only draw further attention to your error.

Check out this guide to create an emunand and turn on exosphere and dns:mitm on your new Emunand and hope for the best for your Sysnand.

https://rentry.co/SwitchHackingIsEasy

If you have Qs swing by here and ask away https://gbatemp.net/threads/switch-noob-paradise-ask-questions-here.488277

 

[Quattro74]

Thanks, Will do. I probably won't change much on this machine. Since I have 7/6 under Burnt Fuses on Hekate, I'm guessing there are too few fuses burnt on my system, and when I try and restore my sysnand backup and boot, the fun will begin there? Maybe there is something that can still be done prior to that first boot? Then I could do a sysnand backup with FW at current level?

 

[lordelan]

You can always boot into your sysNAND with hekate though, regardless of how many fuses you burnt.

 

[mrshasol]

You can always boot into your sysNAND with hekate though, regardless of how many fuses you burnt.

I was following your guide, after finishing the emunand step I decided to read the whole thread just to make sure, and all this talk on fuses got me worried. Would you mind explaining?
My case is, I bought a switch that is already hacked and uses atmosphere on sysnand.
I checked my fuse and it says Burnt Fuses (ODM 7/6): 17-0 (HOS:Unknown)
I'm confused if I should I be doing anything other than the guide? Like worrying about firmwares?
I was planning on after creating the emunand, going to step 4- Mount the USER partition and delete everything on it. Unmount it afterwards. (using hekate to mount, so I can skip the 3- which seems really difficult)

 

[lordelan]

I was following your guide, after finishing the emunand step I decided to read the whole thread just to make sure, and all this talk on fuses got me worried. Would you mind explaining?
My case is, I bought a switch that is already hacked and uses atmosphere on sysnand.
I checked my fuse and it says Burnt Fuses (ODM 7/6): 17-0 (HOS:Unknown)
I'm confused if I should I be doing anything other than the guide? Like worrying about firmwares?
I was planning on after creating the emunand, going to step 4- Mount the USER partition and delete everything on it. Unmount it afterwards. (using hekate to mount, so I can skip the 3- which seems really difficult)

If you already bought it hacked, chances are the person that owned it before already went online with it (while using CFW) so it might be already banned, making it pretty pointless to waste any time with my tutorial.
However, if you can assume that's not the case and it makes sense to clean it up and go online, feel free to do so.
As for the fuses: Don't worry about them, really.
Worst case would be your sysNAND won't boot without any payload (aka the normal/official way) due to the installed firmware being lower than how many fuses are already burnt.
Even in that case you can just use the hekate payload and use the "stock sysNAND" option from the LAUNCH submenu to launch into your (hopefully clean) sysNAND without Atmosphère and any hacks to play online.

One side note though: Using Atmosphère alone won't automatically get you banned or something. At leastt it shouldn't. Installing games with homebrew installers or using cheats or mods online will. To avoid any risk though, don't use a CFW on the NAND you're going online with.

 

[mrshasol]

If you already bought it hacked, chances are the person that owned it before already went online with it (while using CFW) so it might be already banned, making it pretty pointless to waste any time with my tutorial.
However, if you can assume that's not the case and it makes sense to clean it up and go online, feel free to do so.
As for the fuses: Don't worry about them, really.
Worst case would be your sysNAND won't boot without any payload (aka the normal/official way) due to the installed firmware being lower than how many fuses are already burnt.
Even in that case you can just use the hekate payload and use the "stock sysNAND" option from the LAUNCH submenu to launch into your (hopefully clean) sysNAND without Atmosphère and any hacks to play online.

One side note though: Using Atmosphère alone won't automatically get you banned or something. At leastt it shouldn't. Installing games with homebrew installers or using cheats or mods online will. To avoid any risk though, don't use a CFW on the NAND you're going online with.

Thank you for the detailed response!!
The person said he didn't go online, so I hoped it'd work...
It didn't. Once I finished the process (hopefully I did everything correctly) I set up sysnand like new, language etc, and when I tried accessing eshop I got error code
Thanks anyway, great guide!

 

[lordelan]

Thank you for the detailed response!!
The person said he didn't go online, so I hoped it'd work...
It didn't. Once I finished the process (hopefully I did everything correctly) I set up sysnand like new, language etc, and when I tried accessing eshop I got error code
Thanks anyway, great guide!

Maybe the other person applied "Incognito" to the sysNAND? Are u still in contact with him?