A9LH to B9S

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Required Reading

This page is for existing arm9loaderhax users to update their devices to boot9strap.

All future releases of Luma3DS will only be made in the .firm format, which will only be compatible with boot9strap and sighax. This means that to continue receiving the latest updates of Luma3DS, you should use this page to update your installation.

To extract the .7z files linked on this page, you will need a file archiver like 7-Zip or The Unarchiver.

While we believe that custom firmware is safe for online use, there have been online network bans in the past, primarily for cheating and suspicious eShop behavior.

What You Need

To use the magnet links on this page, you will need a torrent client like qBittorrent or Deluge.

Note that, only on New 3DS, secret_sector.bin is needed to revert the arm9loaderhax exploit, which is why it is not needed for the installation of boot9strap on a stock console. If you do not have a New 3DS, you do not need secret_sector.bin.

Section I - Prep Work

For all steps in this section, overwrite any existing files on your SD card.

  1. Power off your device
  2. Insert your SD card into your computer
  3. Copy boot.firm and boot.3dsx from the latest version Luma3DS .zip to the root of your SD card
    • The root of the SD card refers to the initial directory on your SD card where you can see the Nintendo 3DS folder, but are not inside of it
  4. Copy arm9loaderhax.bin from the v7.0.5 Luma3DS .7z to the root of your SD card
  5. Copy SafeB9SInstaller.bin from the SafeB9SInstaller .zip to the /luma/payloads/ folder on your SD card
    • If the luma or payloads folder doesn’t exist, create them
    • Delete any other existing .bin payloads (GodMode9.bin, Decrypt9WIP.bin, Hourglass9.bin, etc.) in the /luma/payloads/ folder on your SD card as they will not be compatible with boot9strap compatible Luma3DS versions
  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. New 3DS Users Only: Copy secret_sector.bin to the /boot9strap/ folder on your SD card

  9. Reinsert your SD card into your device

Section II - Installing boot9strap

  1. Boot your device while holding (Start) to launch SafeB9SInstaller
    • If you see the luma configuration screen instead of SafeB9SInstaller, simply press (Start), then shut down your 3DS and try again
    • If this gives you an error, try either using a new SD card or formatting your current SD card (backup existing files first)
  2. Wait for all safety checks to complete
    • If you get an “OTP Crypto Fail” error, download - aeskeydb.bin, then put it in the /boot9strap/ folder on your SD card and try again
  3. When prompted, input the key combo given to install boot9strap
  4. Once it is complete, press (A) to reboot your device
  5. Your device should have rebooted into the Luma3DS configuration menu
    • Luma3DS configuration menu are settings for the Luma3DS custom firmware. Many of these settings may be useful for customization or debugging
    • For the purpose of this guide, these settings will be left on default settings
    • If you get a black screen, follow this troubleshooting guide
  6. Press (Start) to save and reboot

Continue to Finalizing Setup