Installing boot9strap (MSET9)

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Technical Details (optional)

MSET9 is an exploit for the System Settings application developed by zoogie. It exploits a flaw where the ID1 (the second 32-character folder name inside of the Nintendo 3DS folder, inside of the ID0) can be any name as long as it is 32 characters. Performing a specific sequence of actions results in the console executing the instructions that are encoded into the ID1 folder name, which can be used to grant full control over the 3DS.

Compatibility Notes

This method requires a computer running Windows or Linux. macOS is NOT supported, nor are phones or tablets. If you do not have access to Windows or Linux, you will need to use an alternate exploit.

What You Need

  • The latest prerelease of MSET9 (the Release .zip file)
  • Any 3.x version of Python installed on your computer
    • If you are on Linux, you likely already have Python 3. Check by opening a terminal and entering python3 -V. If this returns a version number, it will work for this guide.

Instructions

Section I - Prep Work

In this section, you will prepare the SD card data necessary for the MSET9 exploit to trigger.

  1. Power on your console with your SD card inserted
  2. Open Mii Maker
  3. Wait for your console to reach the “Welcome to Mii Maker” screen, then exit Mii Maker
    • You may see this screen, which indicates the necessary data has been created
    • If you just reach the normal Mii Maker screen, exit Mii Maker and continue to the next step
  4. Power off your console
  5. Insert your SD card into your computer

  6. Copy everything from the Release .zip to the root of your SD card, overwriting any existing files

    MSET9 root layout

  7. Execute the mset9.py script on the root of your SD card
    • Windows: Double-click mset9.bat
      • If this doesn’t work: hold SHIFT and right-click anywhere in the SD card window, then click the option that opens Terminal, PowerShell, or Command Prompt, then type py -3 mset9.py and press Enter
    • Linux: open a Terminal window, cd to the root of your SD card, then type python3 mset9.py and press Enter
    • You should see a window that says “MSET9 … SETUP by zoogie”
    • You should keep this window open until the end of this page, but if you close it by accident, you can open it again by redoing this step

    Image: MSET9 setup

  8. Type the number corresponding to your console model and version, then press Enter
    • The window should change to this:

    Image: MSET9 setup

    • Ensure that the correct console model and version is displayed
  9. Type 1, then press Enter to setup MSET9
    • If you see “(title.db/import.db) does not exist on SD card!”:
      • Type “yes”, then press Enter
      • Close the MSET9 window
      • Safely eject your SD from your computer
      • Insert your SD card into your console
      • Power on your console
      • Navigate to System Settings -> Data Management -> Nintendo 3DS -> Software -> Reset (visual instructions)
      • Power off your console
      • Insert your SD card into your computer
      • Go back to Step 7 (“Execute the mset9.py script”)
  10. Once the window says “Setting up… done”, safely eject your SD card from your computer
    • Keep the MSET9 window open
  11. Reinsert your SD card into your console
  12. Power on your console

Section II - MSET9

In this section, you will trigger MSET9 to launch SafeB9SInstaller (the custom firmware installer).

These instructions must be followed EXACTLY, so double-check EVERYTHING you are doing to avoid errors!

  1. Hover over the System Settings icon using the D-Pad (do not select it yet)
  2. Power off, then power on your console
  3. Press (A) to launch System Settings
  4. Navigate to Data Management -> Nintendo 3DS -> Extra Data (image)
  5. Do not press any buttons or touch the screen - ensure that you see the Mii Maker icon
  6. With the console STILL ON, and without pressing any buttons or touching the screen, remove your SD card from your console
    • The menu will refresh and say that no SD card is inserted, which is expected
  7. Insert your SD card into your computer
  8. In the MSET9 window, type 2, then press Enter to trigger MSET9
    • You should see “Injecting… done.”
  9. Safely eject your SD card from your computer
    • Keep the MSET9 window open
  10. Reinsert your SD card into your console without pressing any buttons or touching the screen
  11. If the exploit was successful, you will have booted into SafeB9SInstaller

Section III - 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

Section IV - Uninstalling MSET9

In this section, you will remove MSET9 to prevent further issues. (This will not remove the custom firmware that you just installed.)

Do NOT skip this section! If you do, applications may crash unexpectedly and you may encounter errors on the next page!

  1. Power off your console
  2. Insert your SD card into your computer
  3. In the MSET9 window, type 4, then press Enter to remove MSET9
    • You should see “Removing… done”
  4. Close the MSET9 window; you will not need it for any of the upcoming steps

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.

Continue to Finalizing Setup