How to Downgrade Wii From 4.0

Navigate to the Wii Brew website and click on "Download" to save the DOP-Mii application to your computer. Extract DOP-Mii to a directory on your computer by dragging the file and dropping it into a directory on your computer.

Insert an SD card into your computer and format the card as "FAT32." Go to "My Computer" and right-click on the SD card. Click the "Quick Format" and "FAT32" boxes. Click "OK" to format the SD card. Create a folder on the SD card and name it "Apps." Copy the DOP-Mii application folder into the "Apps" folder.

Put the SD card into your Wii and turn it on. Go to the Homebrew Channel and Press "A" to launch the channel. Browse for the DOP-Mii application and press "A" on the channel and press "A" to start the application.

Use the directional pad to move up or down to select the location of the IOS, or internal operating system. If you have Wi-Fi for your Wii, leave the option at "Download IOS from NUS" and press "A" on your Wii mote. If you do not have Wi-Fi, cycle to the right twice to choose the option "Load IOS wad from SD card." Press "A" on the option and it will look in the "WADS" folder on your SD card for the appropriate WAD files.

Choose an IOS for IOS15 v257 when prompted. If you have Wi-Fi for your Wii, leave the option at "Download IOS from NUS" and press "A" on your Wii mote. If you do not have Wi-Fi, cycle to the right twice to choose the option "Load IOS wad from SD card." Press "A" on the option and it will look in the "WADS" folder on your SD card for the appropriate WAD files. Afterwards, you will be prompted to "Apply ES_Identify Patch to IOS36." Press "A" on your Wii mote and it will patch IOS 36. Press "A" to enable NAND Permissions when prompted.

Choose a location of the IOS once more. If you have Wi-Fi for your Wii, leave the option at "Download IOS from NUS" and press "A" on your Wii mote. If you do not have Wi-Fi, cycle to the right twice to choose the option "Load IOS wad from SD card." Press "A" on the option and it will look in the "WADS" folder on your SD card for the appropriate WAD files. Restore IOS15 by repeating the IOS location method and pressing "A" on your Wii mote. Press "A" to return to the Wii main menu once you are given the message everything is successful.

Go to the Homebrew Channel and press "A" to load the channel. Browse for the DOP-Mii application and press "A" to load the channel. Press "A" to on "Load" to launch the application.

Select "IOS36" and press "A" on the Wii mote. You will be prompted to choose another IOS. Choose "IOS36" again when prompted. From the IOS menu that is launched, and delete stub IOSs by pressing the "-" button on the Wii mote. Delete the stub IOSs IOS202, 222, 223, 249 and 250 if they are labeled as "STUBS." You can determine this by cursoring onto each one. On the right side of the screen, it will show "STUB" under "Currently Installed." Reboot to the Wii main menu.

Launch the DOP-Mii application and press "A" on "IOS36." Choose "IOS36" again on the second menu. Choose the IOS version of the Wii system menu you want to downgrade to. Wii system menu 3.0 to 3.3 has IOS 30 v1040 and Wii system menu 3.4 has IOS 50 v4889. Select the appropriate IOS, and press the "+" button on the Wii mote to install it. Press "A" when asked if you would like to accept all patches.

Choose "System Menu" from the main menu of DOP-Mii and press "A." Select the Wii menu version you would like to install that corresponds to the IOS you installed. Press the "+" button on the Wii mote to install the Wii system menu. Restart your Wii and the Wii system menu you chose will run.