How to decrypt 3DS Savefiles from SD Card

ShiningMoonLight

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TLDR: Is possible to decrypt my Ultra Moon save file on the 4GB SD Card that I have so that another 3DS can read the save data.

*Note alternatively briefly I saw a thread that was about trading pokemon from emulator to a 3DS, all I really want is the pokemon on the savefile because on it there's like everything pokemon I had up to 15. Would it be possible to trade / clone them from the original savefile to another?


I have my old 3DS that I dropped as a kid that can only stay on for like 30 seconds before black screening. Happened like 6 years ago and for whatever reason my grandparents sent it to a repair shop which said it was unrepairable given that something was wrong with the mother board. By the time I realized that I could try to see if nintendo could repair I realized they don't even support 3DS repair and even if I did they mostly would have declined given that a third party opened the 3DS up. Anyways I wanted to know if it's possible to decrypt my Ultra Moon save file on the 4GB SD Card that I have. Prevously when looking into this I though it was a dead end given that it was incrypted but just wanted to ask after finding this site.
 
Does it really stay on for 30 seconds? That's very unusual. Most units with problems just don't switch on at all. That suggests the problem might actually be fixable. Does anything different happen if you turn it on with the SD card removed?

Anyway, as you say, the SD card content is encrypted and if you never installed homebrew, you will need to bruteforce the decryption key. This can be done only if you have a QR code for a Mii generated on this unit, or if you have access to another unit that has this unit's Friend code in its Friend list. (The Friend code alone is not adequate – the Friend list needs to have the unit fully registered, with Mii, and not just "provisionally registered".)

If the unit also really works for 30 seconds, you might also still be able to dump the encryption key, but you'll need an ntrboot flashcart. These aren't necessarily very difficult to obtain.
 
Does it really stay on for 30 seconds? That's very unusual. Most units with problems just don't switch on at all. That suggests the problem might actually be fixable. Does anything different happen if you turn it on with the SD card removed?

Anyway, the SD card content is encrypted and if you never installed homebrew, you will need to bruteforce the decryption key. This can be done only if you have a QR code for a Mii generated on this unit, or if you have access to another unit that has this unit's Friend code in its Friend list. (The Friend code alone is not adequate – the Friend list needs to have the unit fully registered, with Mii, and not just "provisionally registered".)

If the unit also really works for 30 seconds, you might also still be able to dump the encryption key, but you'll need an ntrboot flashcart. These aren't necessarily very difficult to obtain.
I know that it stays on for 30 seconds because I am able to get into my Ultra Moon and go into the PC momentarily. So around 30 or so. I don't have it with me given that I'm at college at the moment but from what I remember it didn't even say on for a moment before my grandparents sent it to a random repair shop so I do think they did fix something not sure. I don't remeber anthing different happening when I take the SD card out of the 3DS but i'll have to see if it does when I can.
 
I don't have it with me given that I'm at college at the moment
Well, perhaps you should wait until you get home before starting a thread, then. :glare:

I know that it stays on for 30 seconds because I am able to get into my Ultra Moon and go into the PC momentarily.
It takes a lot longer than 30 seconds for me to start up Ultra Moon and get to the PC. Especially on an old 3DS.

Does that mean if you just leave it on the Home screen it still "black screens" after 30 seconds?
 
Well, perhaps you should wait until you get home before starting a thread, then. :glare:

It takes a lot longer than 30 seconds for me to start up Ultra Moon and get to the PC. Especially on an old 3DS.

Does that mean if you just leave it on the Home screen it still "black screens" after 30 seconds?
That's why I wanted to know if it was possible to decrypt through the SD card because I don't have the 3DS with me.

Not sure about the 30 seconds thing though, I will say I do remember being able to go into the game and look into the PC for a little bit so there some amount of time it can stay on. I didn't modify the 3DS in anyway so it only has that 1 game on the 4 GB SD card btw so maybe that's why its so fast. Also in game my last save was in a pokecenter so there also that.

Yes if I leave it on the home screen it will "black screen" with a generic
"An error has occured. Hold down the POWER Button to turn off power. Then turn it on and try again." on the bottom screen.
 
That's why I wanted to know if it was possible to decrypt through the SD card because I don't have the 3DS with me.
Well, we clearly won't be able to figure out if it is "possible" until you get your 3DS again.

Yes if I leave it on the home screen it will "black screen" with a generic
"An error has occured. Hold down the POWER Button to turn off power. Then turn it on and try again." on the bottom screen.
That is not a "black screen!" That is an "error has occurred" screen! :wacko:

If you're getting that message after 30 seconds on the Home screen, then it is very likely an SD card problem that can be easily solved. But there's not much point in talking about that now since you don't have your 3DS.
 
Well, we clearly won't be able to figure out if it is "possible" until you get your 3DS again.


That is not a "black screen!" That is an "error has occurred" screen! :wacko:

If you're getting that message after 30 seconds on the Home screen, then it is very likely an SD card problem that can be easily solved. But there's not much point in talking about that now since you don't have your 3DS.
K thanks ways, while I don't have the 3DS with me I do have the SD card so if it's the SD card thats the problem then I'll test it in another 3DS and see if it has the same error.
 
K thanks ways, while I don't have the 3DS with me I do have the SD card so if it's the SD card thats the problem then I'll test it in another 3DS and see if it has the same error.
Using your SD card in another 3DS is just going to create new data and is going to make things more confusing. Don't do that.

The only reliable way to test an SD card is to copy everything off the card (Roadkil's Unstoppable Copier is recommended), format the card, and test the empty card with h2testw. If the test passes, then you can just copy everything back again. Sometimes this alone is enough to fix this 30-second crash problem.

If you can't format the card or if h2testw gives you an error, then you just have to copy everything to a new SD card (after formatting and testing the new card).

In the meantime, if you never installed CFW on your 3DS, then there's no way you can decrypt the data on your SD card without your 3DS, if that's what you were thinking. It would take decades of computing power to bruteforce the decryption key without a starting point. You would need a Mii QR code, or a second 3DS with the Friend code in its Friend list.
 
Using your SD card in another 3DS is just going to create new data and is going to make things more confusing. Don't do that.

The only reliable way to test an SD card is to copy everything off the card (Roadkil's Unstoppable Copier is recommended), format the card, and test the empty card with h2testw. If the test passes, then you can just copy everything back again. Sometimes this alone is enough to fix this 30-second crash problem.

If you can't format the card or if h2testw gives you an error, then you just have to copy everything to a new SD card (after formatting and testing the new card).

In the meantime, if you never installed CFW on your 3DS, then there's no way you can decrypt the data on your SD card without your 3DS, if that's what you were thinking. It would take decades of computing power to bruteforce the decryption key without a starting point. You would need a Mii QR code, or a second 3DS with the Friend code in its Friend list.
Thanks for all the help. Just wanted to ask off the unlikely chance if it's possibe for a emulator to read a encrypted SD Card Savefile? Found an old video that in the limited knowlege that I have could work.

TLDW: Video explains how you can use PKHex and PKSM; through having all information of the pokemon of choice copied from the ROM to PKHex to then transfering onto PKSM cloud stored in which you can then copy them back from the cloud into your game.

"How to Transfer POKEMON from EMULATORS to REAL ULTRA SUN or ULTRA MOON on 3DS!!"

-- can't post link's new account --

There clones but feels more legit to me given that there directly from the save file. I'm out of luck for now at least if this isn't possble.

Originally I wanted to use the youtube video incombination with this thread --

"Extract and Decrypt games, NAND backups, and SD contents with ninfs"

-- can't post link's new account --

But after finding out that ninfs stands for (formerly fuse-3ds) I had to throw that idea out the window.
 
TLDW: Video explains how you can use PKHex and PKSM; through having all information of the pokemon of choice copied from the ROM to PKHex to then transfering onto PKSM cloud stored in which you can then copy them back from the cloud into your game.
This sentence makes no sense.

"How to Transfer POKEMON from EMULATORS to REAL ULTRA SUN or ULTRA MOON on 3DS!!"
Emulators like Citra do not encrypt their save data at all. PKSM runs directly on the 3DS and can thereby bypass the encryption.

But after finding out that ninfs stands for (formerly fuse-3ds) I had to throw that idea out the window.
Not sure what that sentence means either. Regardless, ninfs needs the encryption key before it can do anything.
 
This sentence makes no sense.

Emulators like Citra do not encrypt their save data at all. PKSM runs directly on the 3DS and can thereby bypass the encryption.

Not sure what that sentence means either. Regardless, ninfs needs the encryption key before it can do anything.
Ty for the info even if I'm hard to understand.
 
Ok, I really don't want to post this because it make me feel so dumb that I didn't do this in the first place but I will because I don't want people coming to a dead thread hoping for replies.

Finally got my old 3DS XL back and I tried to get a friend code from the old 3ds to my new one so that I could use it for the decryption or whatever it's used for, I got no clue for what.

Anyways I tried getting a QR Code for my Mii but the 3DS wouldn't stay on long enough to do that. Then I tried to do it locally instead after failing the QR Method.

Coincidentally, when looking for infomation online for this specific error where the 3DS says:

"An error has occured. Hold down the POWER Button to turn off power. Then turn it on and try again."

I found a video on youtube saying that it could be caused by the wireless card to disconnect. Which can happen when you dropping your 3DS.

I noticed that when I was trying to get my friend code locally on the top screen corner it wouldn't highlight orange to signifly that wireless is working.

Looking even more into situation's related I found a reddit post talking about how when they turned off wifi for there 3DS the error goes away.

Low and behold this worked for me, my 3DS XL now doesn't do a error after I turned wifi off on my system, with all my problems most likely caused by my wireless card being disconnected.

Kinda annoyied that it was such a simple / easy fix but that how it worked out. Not sure what I'm gonna do at this point but at least now I have a 3DS XL that I can use without wifi.
 
Looking even more into situation's related I found a reddit post talking about how when they turned off wifi for there 3DS the error goes away.

Low and behold this worked for me, my 3DS XL now doesn't do a error after I turned wifi off on my system, with all my problems most likely caused by my wireless card being disconnected.

Kinda annoyied that it was such a simple / easy fix but that how it worked out. Not sure what I'm gonna do at this point but at least now I have a 3DS XL that I can use without wifi.
I already told you exactly what you need to do. :glare: Perhaps it is your wifi card, but if this was a hardware problem with your wifi card, you would probably be seeing different symptoms. I suspect you will find that if you remove your SD card, then your unit will operate even with wifi on.

Problems like this can occur when something goes wrong when the 3DS attempts to write SpotPass data to the card, which happens automatically when it is connected to wifi.

Then I tried to do it locally instead after failing the QR Method.
Also I have no idea what you mean by this.
 
Last edited by Kwyjor,

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