Wii Backup Disc

From WiiBrew
Jump to navigation Jump to search

The Wii Backup Disc is a service disc apparently used inside Official Nintendo Repair shops to transfer personal data like savegames and console settings between Wiis as part of a repair.

While it does not transfer channels, it is capable of transferring enough to be able to redownload the channels from the Wii Shop Channel, which the disc says to do. It is not clear how it does this; the ticket may be resigned, or the whole Wii Shop account might be transferred. The ticket would probably go together with the save data in an RBK file.

"Change WiiId" is mostly useless. WiiId is only used as your Wii Number that you give to your friends so they can send you Wii Mail. When you pick it, it assigns you a new random ID, possibly by incrementing the reset counter.

It also doesn't boot on full bricked Wiis and it's unlikely that it repairs half bricked Wiis since delete all only deletes savegames/settings and not any channel content (Weather/News/Games..) or IOS.

The "DevCerts" are two WAD files on the disc FS called "dummy-cls.wad" and "dummy-loc.wad," both of which have one content which is 0x40 bytes. dummy-loc is empty while dummy-cls has the word "dummy" together with the title ID. The "dummy-loc.wad" file also has a certificate chain including the debug certificates. "dummy-cls.wad" has a ticket which retail Wiis do not accept, therefore it cannot be installed.

While the ID of this disc is 410E (or possibly 408E for some versions), the TMD itself reports it as 1-2, probably to get access to ES_SetUid.


  1. Make sure Priiloader is installed
  2. Enable the Allow TitleID RAAE,408x,410x and Remove IOS16 Disc Error hacks
  3. Disable Block Disc Updates if it is enabled
    1. This is only required to install IOS16, and can be re-enabled after IOS16 is installed from the disc. Note that clicking "Finalize Repair" will delete IOS16, requiring this part to be repeated.
  4. Load the disc from the Disc Channel.

Update partition

The Wii Backup Disc was the only known official application to use IOS16. Because IOS16 is signed by Nintendo, and the update partition of the disc only has IOS16 and boot2v2, homebrew install discs were released that used IOS16 and had a copy of the Wii Backup Disc's update partition.

When RVL-CPU-20 consoles were released, IOS16 became one of the only IOSes that could be downgraded without issues, which resulted in general homebrew also installing IOS16 to get access to the signing bug and patch other IOSes.


Nintendo responded to unauthorized disc and IOS16 usage in the 4.0 update by releasing a stubbed IOS16 (v512). In addition, the System Menu refuses to boot any disc that uses IOS16, with the debug message This must be a backup disk and the standard "An error has occurred" screen, and it blocks the ID 410x in the same area of the code that blocks the Wii Startup Disc, causing it to appear as an invalid disc.

It is unknown how repairs worked after this point, since the debug message would make less sense if a new Wii Backup Disc was released.

Debug SDK

The Wii Backup Disc includes debug SDK libraries, which do not have the same optimized assembly that retail libraries have. In addition, they print more errors, including more source filenames such as NANDOpenClose.c.