All the answers you'll ever need

Basics of asking for help
Provide your sysNAND firmware version

emuNAND firmware version

Your CFW

Version of your CFW (e.g. rxtools nightly, or cakes 138 or reinand 3.2)

Complete error messages

Screenshots if possible

Failed to load NATIVE_FIRM:4
You forgot to put the firmware.bin into sys and the renamed firmware.bin into data inside /rxtools

Your directory should look like this http://onlinemd5.com/


 * /rxTools
 * /data
 * 0004013820000002.bin size:964kb md5:006559E2567DC7DF6C0F1AF17EDD9CE8
 * system.json
 * /lang
 * /nand
 * /sys
 * /patches
 * code.bin
 * firmware.bin size:967kb md5:B99ADF0ADB279712367C06EB83BA9AE6
 * font.bin
 * reboot.bin
 * /theme
 * /0
 * /theme
 * /0

Remove the .sys and .data extensions on the respective files

If this doesn't work you have a newer version of rxTools, use the below.

First delete :/rxtools then copy your version of /rxtools onto :/ then remove the .firm extension size:967kb md5:B99ADF0ADB279712367C06EB83BA9AE6
 * /rxTools
 * /firm
 * 0004013820000002.bin

Can I delete .cia files after I've installed them?
Yes, .cia files are just installers, the actual games reside in :/Nintendo 3DS///title

after they're installed you are free to delete them.

Will accessing the eshop delete my DLC?
It depends, if you've unlinked your NANDS and have emunand on the latest version accessing the eshop should not delete your pirated DLC. This is true for all CFWs.

Why is sysupdater failing 10million times?
The way sysupdater works is that it does a race attack using a GPIO exploit on the gpu to race the arm9 processor during a memory write and jump operation to load its payload into memory and get ran on the arm9 processor for the needed arm9 kernelmode access.

The way this works is the GPU can access almost all of the FCRAM (main memory) and with some clever process kill and start tricks with NS we can get a portion of memory that Process9 is writing on the FCRAM that the gpu can access (process9 is the only process on the arm9 and it controls crypto and nand access and has some necessary syscalls needed to downgrade that i wont go into) now the trick is once process9 starts writing to a portion of memory we have a very very tiny window to load the sysupdater payload into this memory chunk process9 is writing, its 2 lines of code worth of time, very small window, most of the time the gpu loses and you get a lockup or sometimes it half load or loads in a corrupted manner (this is where bricks come from as well as frankenfirmware) which leads to needing to start over, its also why most of the time the program doesn't even load.

this means its pretty much random chance on whether sysupdater will work, i say this because im tired of myths about things you can do to make the process more successful, the only thing you can do is start sysupdater as fast as possible once you get into hbl so the arm9 might still be doing some cleanup or something to slow it down.

Cakes isnt working
Are you using cakes 138?

No?

Are you using >= cakes 139?

File an issue for your problem on Github and then switch to a stable build.

Now that that is out of the way lets move on.

First off if you've changed versions delete the old versions of everything that comes in the cakes download, the /3ds/Cakes, /cakes/patches and Cakes.dat. Keep in mind that if you have autoboot enabled, you need to access the Cakes menu to actually update. To do this just hold L while booting Cakes.

Then consult the below.

you need these

slot0x11key96.bin

O3DS

firmware.bin You must rename the file

cetk

N3DS

firmware.bin You must rename the file

cetk

slot0x11key96.bin goes in :/

firmware/cetk go in :/cakes

You also need to apply the emunand and signature patch "patches" in the Cakes menu.

How do I install FBI/BBM/DevMenu to emunand?
http://pastebin.com/32GdjqKV

FBI gives me this error DESCRIPTION_INVALID_SIZE
You bought a tricky chinaman sd card or you flipped the read only switch on your sd card.

H2testw Test your sd card with this.

Whenever I change my theme with CHMM2 menuhax stops working
Unlink your NANDS.

Stop running chmm2 from the homebrew launcher

Install hblauncher_loader.cia or chmm2.cia (chmm2.cia needs dspfirm.dsc) in emunand and use chmm2 from there.

Or use Howlings theme tool

What is NTR? How do I install it?
NTR is an additional CFW to get additional features. You usually run it along another CFW. You only need to install a .cia and to put the ntr.bin file in the root of your SD card. It gives:
 * region-free
 * virtual memory viewer/editor
 * cheats
 * debugger
 * easy edited romfs loading
 * screenshots
 * savestates (only works until you close the game, at least for now)
 * underclock settings