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Tutorial:Online Play

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Before you get started

There are several items you should prepare before continuing with this tutorial, these are as follows:

  • You'll of course need to own a Wii U
  • A regular SD card (or mini/micro with an adapter) of virtually any capacity
    • Your SD card has to be formatted FAT32 for the Wii U to be able to read it and the allocation unit size is best set to 32KB.
    • On larger SD cards (64GB+) Windows will likely not let you format the card FAT32, to circumvent that use guiformat
  • Your Wii U is able to connect to your WiFi network to be able to dump files via FTP
  • Also make sure the Wii U account you want to dump/use has the "Save password" option checked (auto login)

Preparing your SD card on your PC with the necessary files

If your SD card is formatted correctly it is time to copy the necessary files to it.

I recommend downloading the prepared zip file from - select Wii U only

It pulls (almost) all the required tools from their official sources and neatly packs them into a archive that is ready to be copied to your SD card as is.

Once you have downloaded the archive simply extract the contents right onto your SD card keeping the folder structure of the archive intact.

  • If you use Coldboot Haxchi [Requires purchasing a $7 VirtualConsole Game]:
  • If you want to use Mocha CFW (optionally with Regular Haxchi,) you'll need to install an alternative version of FTPiiU Everywhere:
For easy Homebrew Channel access with Regular Haxchi you will also require to purchase the same $7 Virtual Console Game as mentioned above.

Launching the web exploit and loading up the Homebrew Launcher

The browser exploit might require many tries to get to work.

To make the process of retrieving the required online files easier you can patch a DS Virtual Console game to launch the Homebrew Menu, that way you only need to do the browser exploit once - to patch the DS VC game. If you already own VC Game that's viable or wish to purchase one for $7.00 USD, please see the section "(Optional) Installing Haxchi on top of your DS VC game" later.

If you don't own any of the listed DS VC games nor want to buy any of them then you will have to do the browser exploit twice, once for dumping the otp.bin & seeprom.bin and once for dumping the rest of the files through FTPiiU Everywhere.

This tutorial will cover both routes.

Browser exploit for system update 5.4.0 to 5.5.X

  • Make sure the Wii U is turned off and insert the SD card you have prepared on your PC
  • Boot up the Wii U, launch the browser app and open the curtains by pressing (X) on the gamepad
  • Go into the browser settings and choose Reset save data
  • Open the URL (it is recommended that you bookmark this URL since you might need to try this a couple of times)
  • Press the Exploit button for your firmware and wait.
  • If the Homebrew Launcher loads up you were successful, if your browser is frozen you need to try again (hold the power button until the console turns off and reboot it)
  • This might take a good few tries, resetting the browser save data after every attempt might aid this process.

If you get a FSGetMountSource error trying to load the Homebrew Launcher try going into the mii maker and save a screenshot of any Mii to the sd card, this usually fixes potential inconsistencies in the SD file system that might have caused a conflict.

(Optional) Installing Coldboot Haxchi (CBHC) or Regular Haxchi on top of a DS VC game

Skip to this section if you don't own any of the DS VC titles listed and don't want to buy one.

The following DS VC games are supported:

The cheapest are Brain Age (USA) or Dr. Kawashima's Brain Training (EUR) at around $7.00 USD which can be purchased and downloaded in the eShop app.

The DS VC game must be installed to your System Memory (NAND) - not to your SD or USB.

Assuming you are now in the Homebrew Launcher choose Haxchi from the available apps and once it's launched select the DS VC game you want to install Haxchi over (this will patch the DS VC game to launch the Haxchi Menu instead which gives access to a shortcut for the Homebrew Channel) - Additionally, your Wii U can now be booted with CFW immediately without having to run any exploits.

When it is done you will be booted back to the System Menu and you should see your DS VC game's icon replaced with the "Haxchi /!\ Icon".

After launching this shortcut a menu will appear, unless you're using CBHC, in that case when "autobooting" appears you must press the Home Button for the menu to appear. From this menu you can launch the Homebrew Channel / Launcher. You can also add a Homebrew Channel / Launcher shortcut to your System Menu if you search online - if you prefer to do so. Custom system menu channels will only work when booted into a CFW, not stock firmware.

Using FTP to Dump the required Online Files for CEMU

    If transferring important files over FTP fails, you may instead dump the entire MLC NAND of your Wii U, covered further below, (Click Here)

Using Coldboot Haxchi (CBHC) CFW:

  • Go back to the Homebrew Channel through the Haxchi Shortcut (pressing Home when "autobooting" appears.)
  • While in the Homebrew Channel, launch the nanddumper app.

Using Mocha CFW & Regular Haxchi:

  • Repeat the browser exploit from earlier to get into the Homebrew Channel or open it with Haxchi (by holding A)
  • While in the Homebrew Channel, launch the nanddumper app.

Mocha Note: If Mocha CFW has been launched at any point since the last system reboot, before opening nanddumper, nanddumper will not work. So you will have to reboot your Wii U first to disable Mocha CFW and then get back into the Homebrew Channel through the Browser Exploit.

  • In nanddumper set OTP (1KB) and SEEPROM (1KB) to <yes> and everything else to <no>.

The otp.bin and seeprom.bin will be dumped onto your SD card, afterwards your Wii U will reboot.

Using Coldboot Haxchi CFW (CBHC):

  • Go back to the Homebrew Channel through the Haxchi Shortcut (pressing Home when "autobooting" appears.)
  • Select the option to launch the Homebrew Channel
  • Launch FTPiiU Everywhere from the Homebrew Channel (ensure this is the FTPiiU Everywhere version meant for Haxchi (CBHC), provided earlier in this guide.)

Using Mocha CFW & Regular Haxchi:

  • Repeat the browser exploit from earlier to get into the Homebrew Channel or launch it through Haxchi (by holding A)
  • Once you are back in the Homebrew Channel, select and launch Mocha
  • Make sure Don't relaunch OS is set to <on>
  • Press (A) and you will be booted back into the Wii U System Menu
  • Start the Mii Maker Channel (the browser exploit will have patched it temporarily and it will launch the Homebrew Channel) or launch through Haxchi again.
  • Launch FTPiiU Everywhere from the Homebrew Channel (ensure this is the FTPiiU Everywhere version meant for Mocha & Regular Haxchi, provided earlier in this guide.)

Now it is time to dump the necessary files from your Wii U NAND through FTPiiU Everywhere.

  • FTPiiU Everywhere will tell you on which IP and port it is listening
  • Install FileZilla ( ) or if you prefer WinSCP.
  • Connect to your Wii U via the FTP Client (FileZilla - File --> Site Manager --> "New Site" and add the IP and Port given by FTPiiU
  • Encryption: Only use plain FTP (insecure)
  • Logon Type: Normal
  • User: USER , Password: PASS
  • FileZilla: Once again in Site Manager with your Wii U "Site" selected, Transfer Settings --> ENABLE (and) Set "Maximum Number of Connections" to 1
  • After you opt to Connect, you should now see a bunch of folders, most of them called storage_something after it connects successfully.

    If transferring files over FTP fails, you may instead dump the entire MLC NAND of your Wii U, covered (Here), then return to this area.

'Download' the following files from your Wii U via the FTP client:

  • storage_mlc\sys\title\0005001b\10054000\content\ccerts\ (the entire ccerts folder)
  • storage_mlc\sys\title\0005001b\10054000\content\scerts\ (the entire scerts folder)
  • storage_mlc\usr\save\system\act\800000xx\account.dat

(You will likely have multiple 800000xx folders in storage_mlc\usr\save\system\act - potentially starting as low as 80000001 and having any range of numbering - inspect the account.dat with Wordpad or Notepad++ in each folder if you have multiple to find which one is the account.dat belonging to the account you want to use for Cemu, you will be able to tell by the AccountId field)

If you want to use the friend list app with Cemu to add or remove people you will also need to dump the following folder (depending on the region of your console the exact folder name will differ)

JP: storage_mlc\sys\title\00050030\1001500A

US: storage_mlc\sys\title\00050030\1001510A

EU: storage_mlc\sys\title\00050030\1001520A

Last but not least if you want Miis in games to have heads you will need to dump the following folder:


(Optional) Dumping the MLC NAND of your Wii U instead of using FTP

    You cannot use a USB or too small of an SD Card to do this.
  • SD Card with 16GB free space for White Wii U Models. (White model has 8GB internal storage.)
  • SD Card with 32GB (unless system storage is full) or 64GB free space for Black Wii U Models. (Black model has 32GB internal storage.)
  • Your SD card has to be formatted FAT32 for the Wii U to be able to read it and the allocation unit size is best set to 32KB.
  • On larger SD cards (64GB+) Windows will not let you format the SD as FAT32, to circumvent that use guiformat
  • Launch the Homebrew Launcher with your preferred method explained earlier in this guide.
  • Run the nanddumper homebrew application. Nanddumper will not work with Mocha CFW in use, restart the Wii U if this is the case.
  • Set the options to only dump otp.bin and MLC(8GB/32GB)
  • Press A to begin the dump. The dump will default to the root of your SD card in 2GB chunks.
This process will take some time. Once it finishes, the Wii U will go back to the System Menu.
  • Access the SD Card on your PC. Copy the otp.bin and mlc.bin.part0# files to a preparation area of your choice; there should be 15 parts.
  • The place you copy these to must have double the storage capacity of the mlc.bin.part0# files!
  • If when transfering the mlc.bin.part0# files it says there is an error/corruption, skip that file and transfer the rest.
  • If this happens you will need to try to re-dump the MLC NAND. Afterwards, try to copy the part that was previously corrupt to the location of your non-corrupted parts.
  • Download this zip and extract one of the scripts into the location of your 15 mlc.bin.part0# files.
MLC.bin Joiner Scripts
  • With everything in place, run the script. It will copy the part files and merge them together into mlc.bin (this will take awhile.)
Now we must extract the files from your mlc.bin to where you can browse the files freely.
  • You must now download WFS Tools, unfortunately it is only released for Windows. I do not have a solution for Linux or MacOS users.
WFS Tools Github Releases
  • Extract the tool to your mlc.bin location.
  • Create a new folder named "Extracted" in your mlc.bin location.
  • You will now need to open a CMD window in your mlc.bin location, there are a few ways to do this -
a) In the File Explorer address bar, type CMD and press enter.
b) You can hold shift & right-click the blank area of the current location and open a CMD or PowerShell window.
c) If you're savvy you can cd to the required directory, but I'll leave that to you.
Edit the following command to point to your own "Extracted" folder, the address must be wrapped in " "
    wfs-extract --input mlc.bin --output "C:\Users\*\Desktop\Wii U NAND Backup\Extracted" --otp otp.bin --mlc
  • Once you're sure it's correct, you may paste it into the Command Line Window and send it; it will now begin extraction.
  • To paste a line of text in regular CMD you simply right-click the blank space of the window.
This process will take some time, it will tell you when it has finished. Hopefully no errors arise or you may need to start over.
I recommend keeping your mlc.bin or the Extracted files somewhere safe. CEMU may end up allowing the use of more files in the future!
  • Find the files mentioned in the section above this one and place them into their correct locations for CEMU, mentioned below.

Finishing Steps, placing the Online Files into CEMU

Now all the dumped files need to be copied to the Cemu folder keeping the exact folder structure from the Wii U intact with the exception that storage_mlc becomes just mlc01 (X:\*\Cemu Folder\mlc01).

For example: (make sure your region matches where it should go)

otp.bin: Cemu\otp.bin
seeprom.bin: Cemu\seeprom.bin
Account: Cemu\mlc01\usr\save\system\act\80000001\account.dat (it must always go in 80000001 for Cemu)
CCERTS: Cemu\mlc01\sys\title\0005001b\10054000\content\ccerts
SCERTS: Cemu\mlc01\sys\title\0005001b\10054000\content\scerts
Mii Heads: Cemu\mlc01\sys\title\0005001b\10056000
Friend List USA: Cemu\mlc01\sys\title\00050030\1001500A (you will have to add this to your Game List in General Settings for it to appear.)

Right now Cemu only accepts the user 80000001 which means the account.dat has to go to Cemu\mlc01\usr\save\system\act\80000001\ no matter which numbering it originally had.

Lastly copy the otp.bin and seeprom.bin from your SD card into your Cemu folder (root directory where the Cemu.exe remains).

You should now be able to launch Cemu and select your account as Active account in Options->General Settings->Online.