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title: "Installing boot9strap (safecerthax)"
---

{% include toc title="目次" %}

{% capture technical_info %}
<summary><em>Technical Details (optional)</em></summary>
For technical details on the exploit that you will be using on this page, see [here](https://github.com/MrNbaYoh/safecerthax).

{% endcapture %}
<details>{{ technical_info | markdownify }}</details>
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### Compatibility Notes

safecerthax is compatible with all Old 3DS and Old 2DS devices in all regions on system versions 1.0.0 through 11.14.0.

This exploit will not work on the New 3DS, New 3DS XL, or New 2DS XL. Please ensure that the device you are modding is an Old 3DS, Old 3DS XL, or Old 2DS before continuing.
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### 必要なもの

* The latest release of [SafeB9SInstaller](https://github.com/d0k3/SafeB9SInstaller/releases/download/v0.0.7/SafeB9SInstaller-20170605-122940.zip) (direct download)
* The latest release of [boot9strap](https://github.com/SciresM/boot9strap/releases/download/1.4/boot9strap-1.4.zip) (direct download)
* The latest release of [Luma3DS](https://github.com/LumaTeam/Luma3DS/releases/latest) (the Luma3DS .zip file)

### 手順

#### Section I - Hardware Button Check

{% include_relative include/safemodecheck.txt %}

If the camera did NOT appear, you cannot follow this method. If this is the case, stay on your current firmware and ask [Nintendo Homebrew on Discord](https://discord.gg/MWxPgEp) for help.
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####セクションⅡ－準備

In this section, you will copy the files needed to trigger the safecerthax exploit.

1. パソコンにSDカードを入れます
1. `boot.firm` と `boot.3dsx` をLuma3DSの `.zip` からSDカードのルートにコピーします
  + SDカードのルートとは、Nintendo 3DSのフォルダなどがある最初の項目のことであり、フォルダの中ではありません。
1. `boot9strap`という名前のフォルダをSDカードのルート上に作成します。
1. `boot9strap.firm`と`boot9strap.firm.sha`を boot9strap `.zip` ファイルから解凍し、SD カードのboot9strapフォルダにコピーします。
1. SafeB9SInstaller `.zip` から`SafeB9SInstaller.bin`をSDカードのルートへコピーします
1. デバイスにSDカードを入れます
1. デバイスの電源を入れます

#### Section III - safecerthax proxy

In this section, you will change your Internet connection settings to use a proxy network designed to exploit the System Update feature of your device.

{% include_relative include/addproxy.txt %}
1. デバイスの電源を切ります

#### Section IV - safecerthax

In this section, you will enter Safe Mode (a feature available on all 3DS family devices) where safecerthax will be triggered, which will launch you into the boot9strap (custom firmware) installer.

1. With your device still powered off, hold the following buttons: (Left Shoulder) + (Right Shoulder) + (D-Pad Up) + (A), and while holding these buttons together, power on your device
  + Keep holding the buttons until the device boots into Safe Mode (a "system update" menu)
1. Press "OK" to accept the update
  + There is no update. This is part of the exploit
1. Press "I accept" to accept the terms and conditions
1. The update will eventually fail, with the error code `003-1099`. This is intended behaviour
1. Press "OK" to close the error message
1. Exploitが成功すれば、SafeB9SInstallerが起動されます。
  + If the device freezes or crashes, force power off the device, then retry this section

#### Section V - Installing boot9strap

{% include_relative include/install-boot9strap-safeb9sinstaller.txt %}
{%- include_relative include/configure-luma3ds.txt %}

{% include_relative include/luma3ds-installed-note.txt %}

#### Section VI - Restoring default proxy

{% include_relative include/rmproxy.txt %}

___

[セットアップを完了する](finalizing-setup) へ進みます
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