Upgrade to 4.2 Safely (obsolete)

Warning: This page is now obsolete. The new page that you should use to update is located here

Upgrading to 4.2 easily without the issues of the official update.

This page gives you instructions on how to update your firmware to 4.2. This lets you get the features of those updates without the chance of bricking that the newer update might cause (as long as you haven't previously done nasty stuff to your Wii). Note that a power outage might brick your Wii, however it should be possible to recover if you have a NAND Backup from BootMii.

This update procedure will not delete BootMii, the latest Homebrew Channel, IOS249 nor Hermes' IOS222/223. It will not patch any of the IOSes that it does install, so they will be equivalent to updating through the official channel. It also updates your Wii Shop.

Only perform this step if you are absolutely sure you want the benefits of an upgraded firmware. See the Upgrade FAQ to find out what features have been added.

For more information about upgrading, see the Upgrade FAQ.

What you should install first

What you need

  • SD Card
  • Wii connected to the Internet.

What to download

  • v4.2 Safe Firmware Upgrader from the first post in this thread


  1. If you have not done so recently, make a back up with BootMii before attempting this.
  2. Use the Wii Data Management screen to check you have at least 250 blocks of free space left. Delete unneeded channels or saves until you do.
  3. Remove all GameCube memory cards and controllers.
    • This step is very important. Do not ignore it .
  4. Unrar V4.2 Safe Firmware Updater.rar and copy the contents of the apps folder to sd:/apps.
  5. Start the Homebrew Channel and run v4.2 Safe Updater.
  6. Read the message and push A to accept.
  7. Check that the installer has detected the correct region for your Wii. Push A to accept.
    • If you install an update from the wrong region, it will brick your Wii, so be careful here
  8. The tool will automatically download and install the needed IOSes.
  9. When the tool completes you will be on Firmware 4.2. Push A to exit when prompted.
    • If the tool does not ask you to push A to exit after the installation, it means one of the downloads crashed. You will need to run it again.


  • Will my homebrew still work?
    • Using this guide, the only thing you may need to reinstall after updating is the Homebrew Channel. If you upgraded the HBC recently, you won't even need to do that. All other homebrew listed in this tutorial should continue to work without any need to reinstall anything.
  • New Super Mario Bros. Wii or another game still asks me to update after using this method. Why?
    • NSMBW includes two updates. The first upgrades you to system menu 4.1. The second performs the boot2 update, which is the potentially slightly dangerous update code. To run this game from disc, you will need to use the Avoid Disc Updates method.

What to do next

  • Upgrade your Wii Shop to the latest version. The safe updater fails to do this after the 21 October 2009 Wii Shop Update.
  • Install patches to Avoid Disc Updates.
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