Installing boot9strap (kartdlphax)

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Technical Details (optional)

In order to install custom firmware on our console, we need to get Homebrew Launcher access.

To accomplish this, we can use the Download Play functionality of the game Mario Kart 7, using a 3DS with custom firmware already installed along with a custom game plugin.

This custom plugin will send a hacked payload to an unhacked console, which then exploits the system in order to inject menuhax67, which will allow us to get Homebrew Launcher access.

Once we have Homebrew Launcher access, we can run nimdsphax to install boot9strap.

See here for information about kartdlphax, here for information about menuhax67, and here for information about nimdsphax.

Compatibility Notes

In order to follow these instructions, you will need the following:

  • A second 3DS with custom firmware (the source 3DS) that is the same region as the 3DS you are trying to modify (the target 3DS)
    • The consoles must be USA, JPN, or EUR region consoles
    • The source 3DS can be region changed to match the target 3DS if necessary
  • A physical or digital copy of Mario Kart 7 that is the same region as both consoles
  • An SD card for both consoles

What You Need

Section I - Prep Work (source 3DS)

In this section, you will set up your source 3DS (the 3DS with custom firmware) for delivery of the exploit data to the target 3DS.

  1. Insert the SD card of your source 3DS in your computer
  2. Copy boot.firm from the Luma3DS .zip to the root of the source 3DS’s SD card, replacing any existing file
    • 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
  3. Copy kartdlphax’s plugin.3gx to the following directory on the source 3DS’s SD card, depending on the region of your copy of Mario Kart 7:
    • USA: luma/plugins/0004000000030800
    • EUR: luma/plugins/0004000000030700
    • JPN: luma/plugins/0004000000030600
    • Create the plugins and 00040000... folders if they do not already exist
  4. Eject the SD card and put it in the source 3DS

Section II - Prep Work (target 3DS)

In this section, you will set up the files that the target 3DS will need to install custom firmware.

  1. Insert the SD card of your target 3DS in your computer
  2. Copy boot.firm and boot.3dsx from the Luma3DS .zip to the root of the target 3DS’s SD card
  3. Create a folder named boot9strap on the root of your SD card
  4. Copy boot9strap.firm and boot9strap.firm.sha from the RELEASE .zip to the /boot9strap/ folder on your SD card
  5. Copy SafeB9SInstaller.bin from the SafeB9SInstaller .zip to the root of your SD card
  6. Create a folder named 3ds on the root of your SD card if it does not already exist
    • This folder stores homebrew applications and data; it is different from the Nintendo 3DS folder that the console automatically generates
  7. Copy the nimdsphax folder from the nimdsphax.zip to the /3ds/ folder on your SD card
  8. Copy menuhax67_installer.3dsx from the menuhax .zip to the /3ds/ folder on your SD card
  9. Copy Launcher.dat from the folder for your model and region inside the menuhax .zip to the root of your SD card
  10. Eject the SD card and put it in the target 3DS

Section III - kartdlphax

In this section, you will use Download Play to transfer the exploit data from the source 3DS to the target 3DS, which can be used to install menuhax67, a Homebrew Launcher entrypoint. Your HOME Menu settings will be temporarily inaccessible on the target 3DS while this exploit is active.

  1. Power on the source 3DS
    • If you are prompted to set up Luma3DS, just press START to save the configuration
  2. Once in the HOME Menu, press (Left Shoulder) + (Down D-Pad) + (Select) to bring up the Rosalina menu
  3. Select “Enable plugin loader”
  4. Press (B) to exit the Rosalina menu
  5. Launch Mario Kart 7
    • Ensure that wireless connectivity is enabled
  6. Navigate to Local Multiplayer. A menu should pop up
    • If the screen freezes, hold the power button for fifteen seconds to force power off your console, then try again
    • If you have launched kartdlphax previously, the last selected settings will be loaded. If they are correct, select Use settings and skip the next 3 steps. If they are incorrect, select Change settings and proceed.
  7. Select your target 3DS console type (Old 3DS family or New 3DS family)
  8. Select the following exploit type depending on your system version:
    • 11.16.0: select xPloitInjector (11.16)
    • 11.17.0: select xPloitInjector (11.17)
  9. A confirmation menu will show up. If the settings shown on the top screen are correct, select Use settings
    • If the settings are not correct, press Change settings and modify them accordingly
  10. Select Create Group
  11. Power on the target 3DS
    • Ensure that wireless connectivity is enabled
  12. On the target 3DS, open the Download Play application (), then select “Nintendo 3DS”
  13. Join the group created by the source 3DS
  14. Select “Start” on the source 3DS once it has detected the target 3DS
  15. Once multiplayer has loaded, navigate to Grand Prix -> 50cc -> (any driver) -> Mushroom Cup -> OK
  16. Wait a while (a percentage should be displayed on the source 3DS)
  17. If the exploit was successful, the target 3DS will have booted into the 3DS ROP xPloit Injector
    • If the exploit was not successful, power off the source 3DS and target 3DS and start again from the beginning of Section III - kartdlphax

Section IV - Installing menuhax67

  1. Press (Y) + (D-Pad Down) to install menuhax67
    • The console will automatically power off
  2. Power on your console
  3. Tap on the small HOME Menu settings icon in the top left of the bottom screen ()
    • If the console freezes for a while and then crashes, make sure you have Launcher.dat on the root of your SD card
  4. If the exploit was successful, your console will have booted into the Homebrew Launcher
  5. Launch nimdsphax from the list of homebrew
  6. If the exploit was successful, you will have booted into SafeB9SInstaller
    • If your console freezes on a red screen, hold the POWER button until it turns off, then try running menuhax again by powering on your console and tapping on the HOME Menu settings icon

Section V - Installing boot9strap

In this section, you will install custom firmware onto your console.

  1. When prompted, input the key combo given on the top screen to install boot9strap
  2. Once it is complete, press (A) to reboot your console
  3. Your console should have booted 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, leave these options on the default settings (do not check or uncheck anything)
    • If your console shuts down when you try to power it on, ensure that you have copied boot.firm from the Luma3DS .zip to the root of your SD card
  4. Press (Start) to save and reboot

At this point, your console will boot to Luma3DS by default.

  • Luma3DS does not look any different from the normal HOME Menu. If your console has booted into the HOME Menu, it is running custom firmware.
  • On the next page, you will install useful homebrew applications to complete your setup.

Section VI - Removing menuhax67

In this section, you will use the Homebrew Launcher to remove menuhax67, which will let you access the HOME Menu Settings option normally.

  1. Launch the Download Play application ()
  2. Wait until you see the Nintendo 3DS and Nintendo DS buttons
  3. Press (Left Shoulder) + (D-Pad Down) + (Select) at the same time to open the Rosalina menu
  4. Select “Miscellaneous options”
  5. Select “Switch the hb. title to the current app.”
  6. Press (B) to continue
  7. Press (B) to return to the Rosalina main menu
  8. Press (B) to exit the Rosalina menu
  9. Press (Home) to suspend Download Play
  10. Press the “Close” button on the bottom screen to close Download Play
  11. Re-launch the Download Play application
  12. Your console should load the Homebrew Launcher
    • If your console is stuck on the loading splash screen, you are missing boot.3dsx from the root of your SD card
  13. Launch menuhax67_installer from the list of homebrew
  14. Select REMOVE menuhax67
  15. When you see “done.”, press (A), then press (A) on “EXIT to menu”

Continue to Finalizing Setup