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.
{: .notice--info}
### 必備項目
* 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)
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. 關閉您的主機
#### 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. 如果一切成功的話,您將自動進入 SafeB9SInstaller
+ If the device freezes or crashes, force power off the device, then retry this section