This is thanks to u/perkel

After Many tries and hours I found this users steps and followed them to success (n3ds). I got through the downgrade process and it automatically rebooted without any problems (no black screen or having to remove the sd).

Here's Perkels solution, and I quote:

"- formated my n3ds (had 10.1, updated to 10.3 then format)
- formated SD (32gb kingstone class10) with SD formater (format overwrite + formatsize adjustements)
- downloaded 9.2-20E firmware for N3DS
- checked md5 of above firmware via this site
MD5: 6dcca8fcbc9a28c82c2a4e5182f3acf8
SHA-1: e7c77bf205137167f1f1befa0c4db9d879a21a2e?
- downloaded this systemupdater which julian posted (SULib one) MIRROR

thread where given (if curious):
https://gbatemp.net/attachments/sysupdater-zip.34449/

- downloaded starter kit for homebrew (from smealum site)
- installed TeraCopy to ensure nothing will be damaged via copy/paste on SD card

- put SD to pc
- copy everything lower via teracopy program! (it will show your option when you do it just via copy/paste like normally you do after you install that program)
- copy starter kit folder content to sd card
- copy sysupdater to 3ds folder in your SD card
- copy updates folder to your SD card once you unpacked your downloaded and checked via md5 sum FW
- get your SD card to your 3DS and set up your 3DS (date, time etc.)
- change your theme to something else and back to default (to ensure menuhax will work)
- do browserhax (scan QR code [L+R and then that left sticker] from this site)
- you should go into HomeBrew thanks to above
- choose menuhax manager and install menuhax
- restart your 3DS and hold L to go into homebrewlauncher directly

Once above is done you have properly installed homebrew on 10.3 and it is confirmed that all files are 100% safe to use (that FW you downloaded) and nothing weird should go wrong (it still has that chance though)

Once above was done i started sysupdater from homebrewlauncher.
Since memchunx doesn't work most of the time i had to try 7-10 times before i got #8 success and sysupdater menu.

Then i pressed Y, nothing happened for 3-5 seconds
Then cheking CIA files... or whatever that was for 10-30 seconds
Then it started to install CIA files
Then it got to autorestart in 10 seconds
Autorestarted (NO CRASH)
Booted into 9.2 system without problem perfectly (without taking out SD card)

In other words perfectly updated without single crash (aside from getting into sysupdate menu)

I give my humble thanks to whoever worked on memchunks, julian for this fantastic build and ton of other people that showed me way to ensure everything will work correctly (like teracopy, md5 etc).

Now i have 9.2 and i am wondering what should i do Good thing to wonder about "

Happy Downgrading!

 

[Cataklysm]

Wait wait wait.

So you're telling me that the key to this was using 9.2.20E on a US console?

Really? That's the trick? The US firmware is a brick?

 

[Baccabechoppin]

Wait wait wait.

So you're telling me that the key to this was using 9.2.20E on a US console?

Really? That's the trick? The US firmware is a brick?

Please tell me this is sarcasm.....
Update packs are specific to the region (E updates apply to EUR consoles, U updates apply to US consoles & J updates apply to JPN consoles)

 

[Cataklysm]

Please tell me this is sarcasm.....
Update packs are specific to the region (E updates apply to EUR consoles, U updates apply to US consoles & J updates apply to JPN consoles)

I know that much, but I was just making a dumb assumption because the origin guide never specified a region, just a MD5. When I came up with "E5F40C3B155CFD12EF38BE35D2E81D2E" versus the topic creator, I had some concerns until I realized the region was different.

Guess if this applies to XL n3DS's as well, I guess I'll risk the brick after work on Wednesday.

 

[Baccabechoppin]

I know that much, but I was just making a dumb assumption because the origin guide never specified a region, just a MD5. When I came up with "E5F40C3B155CFD12EF38BE35D2E81D2E" versus the topic creator, I had some concerns until I realized the region was different.

Guess if this applies to XL n3DS's as well, I guess I'll risk the brick after work on Wednesday.

Well this guide was posted by someone with an EUR system so the instructions are going to be more beneficial to them or other people of that region

 

[Cataklysm]

Well this guide was posted by someone with an EUR system so the instructions are going to be more beneficial to them or other people of that region

Right, right. Noted. Hopefully the MD5 for the US region I've got is proper. Will report back with hopefully good results in a short while..

 

[Baccabechoppin]

Right, right. Noted. Hopefully the MD5 for the US region I've got is proper. Will report back with hopefully good results in a short while..

If I remember correctly there's a thread around that contains the correct checksums for each upgrade pack, I can't remember which one it was though (I think it was the one this guide was originally posted in)

 

[Cataklysm]

If I remember correctly there's a thread around that contains the correct checksums for each upgrade pack, I can't remember which one it was though (I think it was the one this guide was originally posted in)

I found and confirmed the md5. Thanks for the tip-off..

 

[mcmanic]

i have a UK/PAL 2ds, this didn't work for me, all steps worked/verfied on downgrade but got the black screen on reboot. Recovery doesn't work, removal of SD, nothing. Off to get another 2ds, good job they are cheapish, lol

 

[Aallaaniaq]

i have a UK/PAL 2ds, this didn't work for me, all steps worked/verfied on downgrade but got the black screen on reboot. Recovery doesn't work, removal of SD, nothing. Off to get another 2ds, good job they are cheapish, lol

Did you try and remove the SD card, then boot up the 2DS?

 

[mcmanic]

yes, after getting the black screen bootup after several attempts of power cycles, after successful install of CIA's and successful reboot after 10secs, thats why was a bit miffed with a black screen

 

[jellybeangreen2]

i have a UK/PAL 2ds, this didn't work for me, all steps worked/verfied on downgrade but got the black screen on reboot. Recovery doesn't work, removal of SD, nothing. Off to get another 2ds, good job they are cheapish, lol

You must have used the wrong firmware files. This happened to me on a N3DS. Make sure you are using the correct firmware package for your region

 

[mcmanic]

they was correct, checked CRC

 

[jellybeangreen2]

Which did you use?

 

[mcmanic]

Honestly cannot remember now, but it was the right one i checked, anyways not to bothered, have another on dispatch for this week and have flashed may items/consoles in the past and this was the 1st to ever go wrong, so not a noob or anything in doing these things. You take the risks and get the rewards or not in this case, lol, till next time.......

 

[vedekandy]

Thanks for this guide! A quick rundown of what I did, using my fresh-out-of-the-box New 3DS XL, which was on firmware 9.5.0-23E:

* Got the Homebrew Launcher working via the web exploit, used it to get Menuhax up and running
* Tried using a different sysUpdater package (from the thread https://gbatemp.net/threads/simple-guide-to-downgrading-your-3ds.407888/) and the 9.2.0-20E firmware for N3DS, using menuhax as the entry point
* Tried well over 50 times with no luck, as it kept freezing at step 5, 6 or 8.
* Decided to change tactics, and tried Steveice10's build (the later one, as he made some changes to it through the day)
* Got constantly stuck with an error about CIA file information, but tried at least 30 times
* Found this guide, followed it to the letter; the VERY FIRST TIME I ran this version of sysUpdater, I got the option to downgrade. Pressed Y, watched as it got to about 10 CIA files in .....
* ....then got the "An error has occured" Nintendo screen. Switched off the power, turned it on, and realised I had a semi-brick - Home menu would crash when loading, the only thing working was the "Sleep" info page.
* Shit myself.
* Booted to recovery mode, updated to 10.3.0-28E.
* Reinstalled menuhax, ran sysUpdater 10 or more times with no luck.
* Used the tip in this thread (https://gbatemp.net/threads/high-success-rate-when-attempting-downgrade-with-sysupdater.408231/) to replace the boot.3dsx file with the sysUpdater, and rename it to boot.3dsx - this saved a LOT of time.
* Around 15-20 attempts later (which by now were a bit quicker) got to the downgrade screen again, watched as it installed at least 20 CIA files
* Ran off to do something else, came back about 3-5 minutes later at most, and the system had rebooted: checking the System Settings shows I have a shiny downgraded N3DS, now on 9.2.0-20E! Woohoo!

I am a little worried that the install went so quickly, but hey, I'm not complaining - it SEEMS to have worked, boots just fine (and I didn't need to remove the SD card, battery or anything else) and doesn't seem to have any issues - granted, I haven't DONE anything with it just yet! Next step is to get some things on here to try out, I guess.

From my experience, and looking around at other threads, I can't help but feel that it's best to downgrade from 10.3.0-28E. I didn't need to format the 3DS as I'd never really done anything on it other than connect it to WiFi (which I've since disconnected - no accidental updates for me, thanks.)

 

[Scresho]

GOT IT!
I LOVE YOU MAN!
N3DS Europe (Not XL)

 

[Aallaaniaq]

Thanks for this guide! A quick rundown of what I did, using my fresh-out-of-the-box New 3DS XL, which was on firmware 9.5.0-23E:

* Got the Homebrew Launcher working via the web exploit, used it to get Menuhax up and running
* Tried using a different sysUpdater package (from the thread https://gbatemp.net/threads/simple-guide-to-downgrading-your-3ds.407888/) and the 9.2.0-20E firmware for N3DS, using menuhax as the entry point
* Tried well over 50 times with no luck, as it kept freezing at step 5, 6 or 8.
* Decided to change tactics, and tried Steveice10's build (the later one, as he made some changes to it through the day)
* Got constantly stuck with an error about CIA file information, but tried at least 30 times
* Found this guide, followed it to the letter; the VERY FIRST TIME I ran this version of sysUpdater, I got the option to downgrade. Pressed Y, watched as it got to about 10 CIA files in .....
* ....then got the "An error has occured" Nintendo screen. Switched off the power, turned it on, and realised I had a semi-brick - Home menu would crash when loading, the only thing working was the "Sleep" info page.
* Shit myself.
* Booted to recovery mode, updated to 10.3.0-28E.
* Reinstalled menuhax, ran sysUpdater 10 or more times with no luck.
* Used the tip in this thread (https://gbatemp.net/threads/high-success-rate-when-attempting-downgrade-with-sysupdater.408231/) to replace the boot.3dsx file with the sysUpdater, and rename it to boot.3dsx - this saved a LOT of time.
* Around 15-20 attempts later (which by now were a bit quicker) got to the downgrade screen again, watched as it installed at least 20 CIA files
* Ran off to do something else, came back about 3-5 minutes later at most, and the system had rebooted: checking the System Settings shows I have a shiny downgraded N3DS, now on 9.2.0-20E! Woohoo!

I am a little worried that the install went so quickly, but hey, I'm not complaining - it SEEMS to have worked, boots just fine (and I didn't need to remove the SD card, battery or anything else) and doesn't seem to have any issues - granted, I haven't DONE anything with it just yet! Next step is to get some things on here to try out, I guess.

From my experience, and looking around at other threads, I can't help but feel that it's best to downgrade from 10.3.0-28E. I didn't need to format the 3DS as I'd never really done anything on it other than connect it to WiFi (which I've since disconnected - no accidental updates for me, thanks.)

Wich susUpdater did you have succes with in the end if i may ask?

 

[wahts]

do anyone have a solution for failed to get cia file info ?

 

[Scresho]

do anyone have a solution for failed to get cia file info ?

did you unpack the zip file of the 9.2.0e files?
All the (over 100) cias have to be extracted to
SD->3ds->sysupdater->updates (i think.. i also had the updates folder in the root of the sd card)

my downgrade worked absolutely fine!

 

[vedekandy]

Wich susUpdater did you have succes with in the end if i may ask?

I used the one on the first page of this thread - Julian's one, SULib version: https://gbatemp.net/attachments/sysupdater-zip.34439/
I don't know if it's the best for everyone, but for me, it worked where others failed to even get to the updating process