Hacking Switch Doesnt Boot to anything after downgrade attempt

[Ariel079]

Let me start this by saying , yes I AM stupid , and no i don't have a full nand backup , only the boot 0/1 backup and no, i cannot boot into the original recovery mode , I get a blue screen and nothing else.

I tried to downgrade from 7.0.1 to 6.2.0 but it effed up , now when i try to boot atmosphere i get error 2021-0004 and i also cant boot into my ofw , all i get is a blue screen, I have no idea what to do , i've exhausted anything I know at this point.

would really appreciate if somebody can help me get out of this mess i stupidly got myself into

 

[Kubas_inko]

1. Why did you try to downgrade?
2. You can rebuild your NAND.
3. Try safe mode.

- Safe Mode (since 4.0.0). Doesn't do much but boot up and download/install an update.
-- Initiated by elaborate key sequence (VolDn + POWER, shift VolDn to VolUp, release POWER.)
-- Displays a spinner block, and a progress bar.
-- If there is a WiFi (or ethernet?) connection saved, it will connect and download an update.
-- If there is an update downloaded/pending, it will install the update.

 

[Ariel079]

1.wanted to go back to 6.2.0 after my switch decided it wanted to update on its own
2.i dont get how to get the keys file as i dont have access to lockpick and hactool doesnt work on 6.2.0+
maybe i'm missing something ?

 

[Kubas_inko]

1.wanted to go back to 6.2.0 after my switch decided it wanted to update on its own
2.i dont get how to get the keys file as i dont have access to lockpick and hactool doesnt work on 6.2.0+
maybe i'm missing something ?

1. But why when there is CFW on 7.0.0/1?
2. Those are bis keys. You can google them.
3. Try safe mode.

- Safe Mode (since 4.0.0). Doesn't do much but boot up and download/install an update.
-- Initiated by elaborate key sequence (VolDn + POWER, shift VolDn to VolUp, release POWER.)
-- Displays a spinner block, and a progress bar.
-- If there is a WiFi (or ethernet?) connection saved, it will connect and download an update.
-- If there is an update downloaded/pending, it will install the update.

 

[Ariel079]

method 3 still gives me a blue screen

 

[Ariel079]

So after using the biskeys with choidjour pc i get an "Invalid NCA Header" problem , any idea on how to fix that ?

 

[Ariel079]

1. But why when there is CFW on 7.0.0/1?
2. Those are bis keys. You can google them.
3. Try safe mode.

Would it be possible to get keys from a switch with the 5.1.0 firmware and use that with hactool and then proceed normally on my switch ? , Maybe something else you could suggest ?

 

[Kubas_inko]

Would it be possible to get keys from a switch with the 5.1.0 firmware and use that with hactool and then proceed normally on my switch ? , Maybe something else you could suggest ?

Not sure now. Just use the biskeydump payload by rajkostos to get the keys.

 

[Ariel079]

Not sure now. Just use the biskeydump payload by rajkostos to get the keys.

I did that but when I try to use it with choidjour it just says "invalid NCA header"

 

[Kubas_inko]

I did that but when I try to use it with choidjour it just says "invalid NCA header"

Maybe that you really need the other keys. Get the other keys and try those. To be honest, I have never done this my self, so I don't know what to do with these errors.

 

[Mambila2001]

You said that your switch updated by itself, haven't you ?

That means that your fuses are burnt and you can not go back to any fw lower than 7.0

 

[Kubas_inko]

You said that your switch updated by itself, haven't you ?

That means that your fuses are burnt and you can not go back to any fw lower than 7.0

Wrong. He can always go to any FW. He just needs to boot through RCM.

 

[Mambila2001]

Wrong. He can always go to any FW. He just needs to boot through RCM.

My bad then. How does that work though ?

 

[Kubas_inko]

My bad then. How does that work though ?

If you have fewer fuses than what your FW needs and you want to preserve them, you have to bypass the fuse check by booting through custom bootloader, thus RCM.
If you have more fuses than what your FW needs, it won't boot no matter what, unless you bypass the fuse check by booting through custom bootloader, thus RCM.

 

[Ariel079]

If you have fewer fuses than what your FW needs and you want to preserve them, you have to bypass the fuse check by booting through custom bootloader, thus RCM.
If you have more fuses than what your FW needs, it won't boot no matter what, unless you bypass the fuse check by booting through custom bootloader, thus RCM.

Well apparently mine won't boot in any case , so my best bet (and correct me if I'm wrong) would be to try and force a downgrade to 5.1.0 with the keys I'll jump from the 5.1.0 switch won't it ?

 

[Kubas_inko]

Well apparently mine won't boot in any case , so my best bet (and correct me if I'm wrong) would be to try and force a downgrade to 5.1.0 with the keys I'll jump from the 5.1.0 switch won't it ?

If they are biskeys, the have to be yours (or idk.). Just try everything (own keys, someones keys, some other keys)

 

[Ariel079]

If they are biskeys, the have to be yours (or idk.). Just try everything (own keys, someones keys, some other keys)

Yeah at this point I don't have much to lose anyway

 

[Kafluke]

My bad then. How does that work though ?

Read this https://gbatemp.net/threads/psa-stop-downgrading-unless-you-know-what-youre-doing.531861/

 

[Ariel079]

If they are biskeys, the have to be yours (or idk.). Just try everything (own keys, someones keys, some other keys)

Happy to report I unbricked my switch by rebuilding my nand but instead of using my own keys.txt file I populated one from a friend's switch and then proceeded normally as stated in the tutorial and nowy switch is working on version 5.1.0.
Never doing stuff like this with no backup again

 

[Kubas_inko]

Happy to hear that.