3DS:ntrboot/usage

This article is for general guidance on how to use ntrboot for various purposes. For instructions specifically on installing custom firmware, follow our custom firmware installation guide's page.

ntrboot allows .firm payloads to run entirely independent from the console's firmware, so it can be used to fix all known software issues. However, it can also cause the same issues if used incorrectly - be careful to get things right the first time, as the instructions may be harder to follow after a failed attempt.

If you are a power user, you may wish to always use GodMode9 as the default boot.firm loaded by your flashcart. You will always have its functionality available this way, and GodMode9 is capable of chainloading into other payloads as needed through the FIRM Options... menu of a .firm file.

Reinstalling the bootloader

This section only installs boot9strap and is not a replacement for a full CFW install. If your system does not yet have custom firmware, follow the link at the top of the page.

If you have installed a bootloader that cannot boot the system normally with CFW otherwise working, you can run GodMode9, SafeB9SInstaller, or OpenFirmInstaller via ntrboot to install a valid bootloader in its place. The following instructions will have you run SafeB9SInstaller through GodMode9 to avoid an issue with the Checking microSD card... step of SafeB9SInstaller.

What you need

• The latest release of SafeB9SInstaller (the .zip file that isn't the source code)
• The latest release of GodMode9 (the .zip file that isn't the source code)
• The latest release of boot9strap (the boot9strap-#.#.zip file - not ntr-devkit, ntr, or devkit)

Instructions

Section I - Prep Work

1. Insert the flashcart's SD card into your computer
2. Copy SafeB9SInstaller.firm from the SafeB9SInstaller .zip to the root of your SD card
3. Copy GodMode9.firm from the GodMode9 .zip to the root of your SD card and rename it to boot.firm
4. Reinsert the flashcart's SD card into your flashcart
5. Insert the console's SD card into your computer
6. Create a folder named boot9strap on the root of your SD card
7. Copy boot9strap.firm and boot9strap.firm.sha from the boot9strap .zip to the boot9strap folder on your SD card
8. Reinsert the console's SD card into your console

Section II - ntrboot and installation

1. Use your magnet to find the spot on your device that triggers sleep mode
2. Power off your console and insert the flashcart
3. Set the magnet into place (or on an old 2DS, enable the sleep mode switch), then hold START, SELECT, and X and press POWER - continue to hold the other three buttons for around five seconds
   • This may take a few tries to work since the positioning is awkward - if you boot into anything other than GodMode9, power off and try again
4. Remove the magnet or disable the sleep mode switch - if the exploit was successful, you will have booted into GodMode9
5. If asked, press B to deny setting RTC and/or doing an essential files backup, then navigate to SafeB9SInstaller.firm and press A, choose FIRM Options... and then choose Boot FIRM.
6. When prompted, input the key combo given on the top screen to install boot9strap
7. When the install is complete, hold the power button to forcibly power off your console
8. Depending on why you had to reinstall boot9strap, you may also want to follow Finalizing Setup from the CFW install guide at this point

Recovering from software bricks

If your console has been bricked not due to hardware damage, then you can recover the system with ntrboot by loading GodMode9. From there, you can use needed tools depending on the specific issue - the most common three are listed as follows.

Recovering from an unusable NAND

See how to restore a NAND backup for more specific instructions. If you do not have a NAND backup, you will instead need a CTRTransfer, a manual CTRTransfer, or help from the Nintendo Homebrew Discord, depending on how severe your issue is. If you have a copy of essentials.exefs backed up, then even in the worst-case scenario you will only need a manual CTRTransfer.

Recovering from corrupted FIRM partitions

Reinstall boot9strap, even if you see a BootROM error when powering on your console.

Issues with uninstalling custom firmware

If you have a NAND backup from when you first installed custom firmware, restore it. If you do not, then reinstall boot9strap and then follow Restoring / Updating CFW to make the system usable again.

Installing CFW in edge cases

In cases where your system cannot normally install CFW, such as when important buttons other than START+SELECT+X+POWER are broken or the console has software issues that break parts of the system used in the exploits, ntrboot can still be used to install CFW.