Warning

Use this at your own risk. Messing with the isfs superblocks is dangerous and can brick your Wii U. Make sure to make a SLC backup before installing isfshax. If something goes wrong, you will need defuse to restore this backup. The superblock linked here was tested and confirmed working. Installing an broken superblock will brick your Wii U.
Also while ISFShax is installed standby services and with that the quick start menu won't work. (Your Wii U will hang once you turn it off till you remove power if standby services are enabled).
Also keep in mind: if you are restoring an old SLC backup, which was taken before installing ISFShax, ISFShax will remove by restoring that backup.

To protect against Nintendo pushing a boot1 update (very unlikely, but you newer know), which would brick a console with ISFShax, system updates get blocked by the wafel_isfshax_patch.ipx plugin. If you need to do a system update, you can use the v1.0 of said plugin, which doesn't contain the update block. Game updates are not affected.

Update

04.04.2024 - Add Fastboot
13.03.2024 - System updates now get blocked by the wafel_isfshax_patch.ipx plugin.
29.12.2023 - Standby Services are now supported. For that to work you need to have the latests ISFShax superblock installed and need to use the latest minute fw.img and wafel_core.ipx. Also autoboot needs to be enabled.

What is this for?

ISFShax exploits boot1 with specially crafted ISFS (the filesystem of the SLC) superblock. Once it is installed ISFShax provides similar capabilities to defuse once it is installed. Since it launches before IOSU, so it can be used to apply early patches to IOSU and can be used to fix most bricks. But it won't protect you of bricks caused by: breaking boot1, seeprom bricks or installing a broken ISFShax superblock. ISFShax also doesn't help you if you already bricked the Wii U.
Usecases are:

• Rebuilding / upgrading the MLC
• Removing 64GB MLC limit and disabling SCFM
• Brick protection (e.g. before doing region change)
• Cold booting redNAND (useful when when the eMMC is failing)
• It gives a minimal CFW, which can launch old homebrew using the homebrew launcher (not sure how usefull since we have Aroma and Tiramisu)
• Stop the Wii U from turning the Tablet on during boot (using a stroopwafel plugin)

Choosing the Exploit

There are multiple ways to launch the ISFShax installer:
If you already have Tiramisu or Aroma installed and can launch it follow the Instructions for [Tiramisu]
If the Browser still works and you can launch the browser exploit u.wiidb.de follow the Instructions for [Browser]
If you can't access the Browser, but Settings still work follow Instructions for [DNSpresso]
If you your Wii U crashes in the initial setup on Mii creation follow Instructions for [DNSpresso]
If your Wii U can't launch the browser anymore or can't connect to the internet follow the Instructions for [UDPIH]
Steps without a prefix apply to all.

Preparing the SD card

Make sure the SD card is formatted FAT32 (already the case if you are using it for Tiramisu). You can use guiformat for that.

Get the following files and put them in the root of the SD. Choose the release tagged with "Latest" for each.

1. ISFShax installer (ios.img) from https://github.com/isfshax/isfshax_installer/releases
2. ISFShax superblock.img and superblock.img.sha from https://github.com/isfshax/isfshax/releases
3. Put the stroopwafel wafel_core.ipx from https://github.com/jan-hofmeier/stroopwafel/releases in wiiu/ios_plugins
4. Put the wafel_isfshax_patch.ipx stroopwafel plugin from https://github.com/isfshax/wafel_isfshax_patch/releases in wiiu/ios_plugins
5. [Tiramisu | Browser | DNSpresso] minute fw_encrypted.img from https://github.com/jan-hofmeier/minute_minute/releases and rename to fw.img
6. [Browser | DNSpresso] fw_img_payload from https://github.com/wiiu-env/fw_img_payload/releases extract the zip and put the wiiu folder, containing the payload.elf on the SD
7. [DNSpresso] Extract the root.rpx from https://github.com/wiiu-env/PayloadFromRPX/releases and rename it to launch.rpx and place it in the root of the SD card
8. [UDPIH] minute fw.img and boot1.img from https://github.com/jan-hofmeier/minute_minute/releases
9. [UDPIH] recovery_menu from https://github.com/jan-hofmeier/recovery_menu/releases

The structure on the SD should look like this:

boot1.img (only for UDPIH)
fw.img
ios.img
recovery_menu   (only for UDPIH)
superblock.img
superblock.img.sha
wiiu
    ios_plugins
         wafel_core.ipx
         wafel_isfshax_patch.ipx

Launching into minute

This step heavily depends on the used Exploit.

Spoiler: Tiramisu

1. Hold B on the Gamepad while booting (if coldboot is enabled) or launching the H&S app
2. A black and white menu should show up asking you to choose a payload.
3. Select fw_img_loader

Spoiler: Browser

1. Open the Browser and browse to u.wiidb.de
2. Click on "HAXX"

Spoiler: DNSpresso

If you can a access the settings just follow these instructions (you already have the right files on the SD): https://gbatemp.net/threads/dnspresso-a-wii-u-dns-exploit.642123/
If you are stuck on the Mii creation in the Inital setup:

1. If you already connected your Wii U to your AP / Router, turn the AP / Router or the Wifi on it off.
2. When the setup asks you if you already have a NNID, say yes (even if you don't have one)
3. Now it tries to connect to the Internet, but will fail and ask you to take you back to the Wifi settings, follow back to thge settings.
4. Turn your Router / AP on again and give it time to start.
5. If you don't already have your Wifi configured there, connect to it now, but enter a wrong password.
6. Edit your wifi connection and configure 85.215.57.182 as Primary DNS, if you entered a wrong password before set the right one now.
7. Press (B) Back and select Connection Test.

Spoiler: UDPIH

1. Load the recovery using UDPIH: https://gbatemp.net/threads/udpih-usb-host-stack-exploit-recovery-menu.613369/ (don't replace the recovery_menu)
2. Unplug the Pico
3. select the "Load BOOT1 payload" and proceed. (If you don't have screen output: 18x eject, 1x power, 1 eject, 1 power)

Now you should see the minute main menu. If not something went wrong, make sure you have the correct fw.img file on the SD.
In minute you move the cursor with the power button and enter with the eject button (swapped compared to the recovery menu).

Note minute only outputs 1080p through HDMI, no picture on the gamepad, and nothing on the analog outputs.
Some people reported that the screen output is not working for them when minute was loaded from the recovery. If you made sure nothing else is the problem (right fw.img, TV supports 1080p HDMI), you can still follow along blindly by pressing the approriate buttons. Make sure to wait long enough between the presses, so the system has time to load. Without display output skip the first backup and go directly to Installing ISFShax.

Backup

1. Navigate to Backup and Restore
2. Dump SEEPROM & OTP
3. Dump SLC.RAW
4. Return to Main Menu

Installing ISFShax

1. Choose Boot `ios.img` (5x Power, 1x Eject)
2. Now the ISFShax installer should launch (this takes a few seconds)
3. Follow the Instructions on the screen, the buttons are the same as in minute. (3x Eject, 1x Power, 3x Eject)
4. The console should now turn off.
5. [Tiramisu | Browser | DNSpresso] replace the (encrypted) fw.img on the SD with the fw.img (NOT the encrypted one) from https://github.com/jan-hofmeier/minute_minute/releases
6. If the install was successfull the Wii U should directly start into minute once you turn it on again.

Backup ISFShax

Dump the SLC.RAW again. This will overwrite the previous SLC.RAW file on the SD. This is required if you need to restore the SLC for unbricking, without loosing ISFShax. Keep that backup in a safe place.

Booting

If you came here from the redNAND or the MLC rebuild tutorial continue with that tutorial now.

For now your Wii U needs the SD card to boot. From there it loads minute (fw.img), which then applies the required patches from SD card. (IOSU needs to be patched, so it doesn't fall over the ISFShax superblock).
To boot into the Wii U OS select Patch (sd) and boot IOS (slc)

Aroma / Tiramisu

1. To install Aroma or Tiramisu put the corresponding files on the SD.
   Tiramisu: https://tiramisu.foryour.cafe/
   Aroma: https://aroma.foryour.cafe/ (You don't need to have install Tiramisu to have Aroma, also the FTPiiU plugin will become handy later)
2. Put the wafel_payloader.ipx in the ios_plugins folder https://github.com/jan-hofmeier/wafel_payloader/releases
3. Put the root.rpx from PayloadFromRPX in the wiiu folder on the SD https://github.com/wiiu-env/PayloadFromRPX/releases

Note: if you are already coldbooting Tiramisu / Aroma via the PayloadLoaderInstaller, you have to disable the coldboot in the PayloaderLoaderInstaller first. For more detailed instructions on this, see this post by ZaMaster: https://gbatemp.net/threads/how-to-set-up-isfshax.642258/post-10343876

Booting without SD

This step is optional but highly recommended. Now the Wii U doesn't show anything on the screen without the SD. That could lead to confusion if the SD ever gets lost or corrupts.
To make it from the internal memory we need to install the minute fw.img and the ios_plugins to the SLC. This can be accomplished using FTPiiU Everywhere, which can be launched from Tiramisu and is already part of the Aroma Package (enable Everywhere in the settings) or you can use the haxcopy homebrew https://github.com/mackieks/haxcopy/releases
Using haxcopy is recommended for most users, but if you copy a wrong plugin to the slc or need to delete one for whatever reason you still have to use FTP for that.

Spoiler: haxcopy

1. create a folder hax on the SD card (this will be copied to the slc)
2. copy the fw.img to the hax folder
3. create a subfolder ios_plugins in the hax folder
4. rename the wafel_core.ipx to 0core.ipx and copy it to the hax/ios_plugins folder
5. rename the wafel_isfshax_patch.ipx to 6isfshax.ipx and copy it to the hax/ios_plugins folder
6. if you want to coldboot aroma or tiramisu, rename the wafel_payloader.ipx to 9payldr.ipx and copy it to the hax/ios_plugins folder
7. If you need any other plugins like the wafel_unlimit.ipx, you have to rename and copy it to the hax/ios_plugins folder
8. Copy the haxcopy app to the wiiu/apps folder (like you usually install homebrew)
9. Put the SD in the Wii U and run haxcopy to copy the hax folder to the slc.

Spoiler: FTP

On Aroma you have to make sure access to system files is enabled:

1. Open the Aroma Plugin Configuration Menu using L + Down + SELECT (-) on the GamePad or Pro Controller (or B + Down + Minus (-) for WiiMotes)
2. Open the FTPiiU option, then settings and set ‘Allow access to system files’ to ‘true’ by pressing A

Uploading the files:

1. (Tiramisu only) Make sure FTPiiU Everywhere is running on the Wii U
2. Using a FTP client on the PC browse to /storage_slc/
3. If you see a scfm.img file and sys folder go into the sys folder. If you see a bunch of folders (config import logs proc rights security title tmp) just go to the next step.
4. create a subfolder hax and enter it
5. Make sure your FTP client is in binary mode (not ASCII mode)
6. upload the minute fw.img to the /storage_slc/sys/hax folder
7. create another subfolder ios_plugins in /storage_slc/sys/hax
8. enter that /storage_slc/sys/hax/ios_plugins folder
9. rename the wafel_core.ipx to 0core.ipx and upload it
10. rename the wafel_isfshax_patch.ipx to 6isfshax.ipx and upload it
11. if you want to coldboot aroma or tiramisu, rename the wafel_payloader.ipx to 9payldr.ipx and upload it
12. If you need other plugins like the wafel_unlimit.ipx, you have to rename and upload them too

Now the Wii U should autoboot if no SD card is inserted.
If a SD card is inserted the minute menu should show up (even if the SD doesn't contain a fw.img). In that menu you can select the Patch (slc) and boot IOS (slc) to load the plugins from the slc and boot (no need to have them on the SD anymore).

The Wii U will first try to load the fw.img from the SLC and if that fails it falls back to the SD.
If you installed a broken fw.img which doesn't load, you can force isfshax to load the fw.img from sd by repeatly pressing power till the menu shows up.

Warning: A factory reset will delete the hax folder. Without the fw.img on the SD the Wii U will then just have a black screen with a orange LED

Optional Autobooting with SD

To make the Wii U autoboot with an SD card inserted you need to create the file sd:/minute/minute.ini with the following content:

[boot]
autoboot=1
autoboot_timeout=3

You can adjust the timeout (in seconds) to your liking. The autoboot option specifies which entry from the minute menu will be loaded. 1 corresponds to Patch (slc) and boot IOS (slc), which loads the ios_plugins from the SLC. If you haven't installed them to the SLC or want to load them from the sd for another reason you can change that value to 3 which corresponds to Patch (sd) and boot IOS (slc)

As an Alternative check out the Fastboot option below.

Optional: Fastbooting (Advanced)

To make the Wii U boot as fast as possible, without showing minute, you can now use the fw_fastboot.img. This won't work with redNAND
It is hardcoded to go straight to the first option (booting the slc, with patches from SLC). It won't display anything and ignore any autoboot configuration in the minute.ini.

1. First make sure the system can boot using the first option in minute. (see booting without SD)
2. Replace the the fw.img in the hax folder on the SLC with the fw_fastboot.img (renamed to fw.img)

In case you ever get stuck and need to load the full minute from SD you can do this:

1. Place the minute fw.img on the SD card
2. repeatedly press the power button until the minute menu shows up on the screen.

Uninstalling ISFShax

DON'T just restore an older SLC backup, as that would break SCFM!

• Make sure your Wii U doesn't depend on any patches (linke wafel_unlimit_mlc.ipx or redNAND). You can check that by booting with only the wafel_core.ipx and the wafel_isfshax_ipx plugins in the ios_plugins directory on the SD and using the Patch (sd) and boot IOS (slc) option
• Delete the /storage_slc/sys/hax folder if you set up the slc booting
• run the ISFShax installer again from minute and follow the on screen instructions to uninstall.

Credits

• @rw-r-r_0644 for finding and implementing isfshax
• @GaryOderNichts and ashquarky for their direct contributions and help
• @vgmoose for all the support and for the Wii U that replaced the one Idestroyed during early isfshax testing
• @Maschell for his help and all other contributions to the Wii U scene
• hexkyz for the warmboot boot1 exploit which made all of this possible
• @shinyquagsire23 for de_Fuse, minute and stroopwafel
• Salt Team for the original minute CFW
• dimok789, FIX94 and others for the iosuhax CFW
• fail0verflow for mini
• and all other contributors to the Wii U scene!

 

[Vanya623]

Hello everyone I have a problem, I recently updated minute with plugins, now it can't find otp, where should I put otp now?

 

[SDIO]

If you are not defusing, it shouldn't need the otp. What error are you getting exactly? Make sure both minute and stroopwafel are updated

 

[Vanya623]

no way, it gets stuck on "Searching for OTP in patch..." and "Searching for OTP in plugins..."

 

[SDIO]

That sounds like you have an old minute. If you copied it to the SLC before, press the power button repeatedly, so minute gets loaded from SD, then it should boot and you can replace it on the slc

 

[Phantaemon]

Hello, victim of the 160-0103 error here. My console boots and gets the error only when attempting to open the Parental Controls app. Gonna attempt ISDShax as I came from the redNAND tutorial.

This part confuses me "Make sure to make a SLC backup before installing isfshax. If something goes wrong, you will need defuse to restore this backup." as I literally do not know how to do that. I can only get my SD card later today so this isn't urgent, but can anyone tell me how to do said backup? This is a step I cannot afford to skip as I'm trying to make my console work again long enough for me to backup all my save data, games, and everything else I can.

 

[SDIO]

The guide includes creating the slc backup at the appropriate time. Defuse would require soldering, but I wouldn't worry about that now. I made the disclaimer when ISFShax was released. After a few months now in the field it proofed it self rock solid.
Only one brick so far, and that was probably due to a problematic SD slot.
If you are getting 160-0103 it's definitely safer to install ISFShax than not.
You can also do a complete backup image auf the console with the nand dumper: https://github.com/wiiu-env/wiiu-nanddumper-payload/releases
But it is probably best to first install ISFShax and then worry about the rest later.

 

[XDeltaOne]

Hi, I have a question, what can you do with a redotp? Or what is it good for?

 

[SDIO]

You can use it to boot a redNAND form another console. For that you would use the format redNAND on another console, enable all 3 partitions in the rednand.ini and have the source consoles otp as redotp.bin. Minute will then use the redotp.bin and pass it to stroopwafel to use it in place of the real otp. Also minute patches in the SEEPROM key of the console you are running on, so it can still read the seeprom. But what doesn't work yet is use the USB storage from the other console, because part of the key for that is in the SEEPROM. For that we would also need seeprom redirection, but so far no one requested that.

 

[Phantaemon]

The guide includes creating the slc backup at the appropriate time. Defuse would require soldering, but I wouldn't worry about that now. I made the disclaimer when ISFShax was released. After a few months now in the field it proofed it self rock solid.
Only one brick so far, and that was probably due to a problematic SD slot.
If you are getting 160-0103 it's definitely safer to install ISFShax than not.
You can also do a complete backup image auf the console with the nand dumper:
But it is probably best to first install ISFShax and then worry about the rest later.

Hello! Thank you for your answer.
turns out the error affected parental controls, and parental controls only. As I hadn't seen your answer I straight up installed Aroma and dumped everything I could. Using the payload you linked, as it was also used in the wiiuhacks tutorial.
Only thing I didn't do was the full MLC backup as I feared it would brick something due to the parental controls title being affected.

I didn't know that restoring a backup would require me to solder things. Does it also apply to things non ISFShax related? I can unfortunately not do ANY kind of soldering at the moment: lack of experience, appropriate environment and tools oblige.

I know that the risk is low now but I kinda suck at anything that involves partions (NONE of my linux installations went right when done by myself and it was. always. a partition issue. for some reason.) so I'm kinda scared of attempting anything else.

My SD is 64gb, a sandisk extreme one, it will definitely fit everything needed if I really *have* to.
I really want to keep that wiiu so that I can at least dump games and play them on Cemu instead. Given that I have Aroma and have dumped absolutely every save file, online data and the 4 things that nanddumper turns on by default (as prompted by the wiiuhacks tutorial) do you think it would be beneficial to me to attempt ISFShax?

 

[JeremyKO]

Hi ! can we restore mlc.bin.partXX with this?
(functional mlc.bin.partXX, obviously)

 

[SNBeast]

no way, it gets stuck on "Searching for OTP in patch..." and "Searching for OTP in plugins..."

I had this issue too with up-to-date software. I fixed it by taking OTP backups again, then of course updating minute on SLC as advised.

 

[CrazySquid]

I was wondering if UDPIH is still working with ISFSHax? The reason I want it is to run a MLC check, because Nintendo eShop freezes every time I want to open it.

Nevermind, it works!

Weird... it gave me 0 errors on both SLC and MLC... it's not a corruption issue then.

 

[V10lator]

Nintendo eShop freezes every time I want to open it.

it's not a corruption issue

Maybe just try reinstalling the eShop with NUSspli (download & install in a single run, as the eShop isn't paid software this won't even give you a fake ticket).
if that doesn't help download, zip and upload the log folder (storage_slc:/sys/logs), please.

 

[SDIO]

I didn't know that restoring a backup would require me to solder things. Does it also apply to things non ISFShax related?

If you don't have ISFShax installed and it bricks you might need to solder depending on the brick.
Since ISFShax runs much earlier, you can use that to unbrick from much more situations without soldering.
Restoring a backup is almost never necessary. But if you wanted to restore on you would either install ISFShax or would have to solder defuse if you can't install ISFShax anymore.

do you think it would be beneficial to me to attempt ISFShax?

Yes as it would prevent your console becoming a useless brick.

I had this issue too with up-to-date software. I

Then you didn't have the latest software as the latest minute doesn't even contain that string. You probably have an old minute on the SLC and only updated the one on the SD.

Also the otp.bin on the SD isn't even touched if the console isn't defused.

can we restore mlc.bin.partXX with this?

Yes, but you likely won't be happy with that.
You would have to write out to the mlc partition on the redNAND and then do the restore.
But since there is scfm on the slc, it would be inconsistent and might not even boot. If the backup was made with the recovery menu, then you could just delete the scfm.img from the SLC.
If it was backed up by other means, then you would also have to restore the scfm.img from the SLC backup. And at the moment there isn't a good way to do that. Ofc you could restore the SLC then also, but if that doesn't contain isfshax, you would lose ISFShax and if it goes wrong it won't boot and you lost ISFShax to fix it.

 

[SNBeast]

Then you didn't have the latest software as the latest minute doesn't even contain that string. You probably have an old minute on the SLC and only updated the one on the SD.

I repeatedly made sure that everything (ISFShax, minute, my stroopwafel build with USB_SHRINKSHIFT and related compilation fixes, stroopwafel plugins) was up to date. Launching into minute by mashing power and then booting the stuff I updated on SD by selecting option three would always hang at searching for OTP, until I made the backups again.

That is, when I took the backups and then backed out of the menu and tried booting, it worked then and thereafter.

 

[CrazySquid]

Maybe just try reinstalling the eShop with NUSspli (download & install in a single run, as the eShop isn't paid software this won't even give you a fake ticket).
if that doesn't help download, zip and upload the log folder (storage_slc:/sys/logs), please.

Reinstalling didn't change, still freezes.
Here is the logs (the folder has been deleted so it's less of a hassle to find relevant info):


EDIT: Just to add more info, I think this was failing before, but I did a default setting reset for my console ("formatting" from system settings). After that I set up a user without NNID.
I installed Pretendo, and set up a PNID to that user.
After all of that is done, I tried to launch the eShop and it doesn't work, but I believe it wasn't working before either, I don't recall fully.

 

[SDIO]

@CrazySquid maybe try reinstalling OSv10, in case any of the libraries damaged.

@SNBeast First the message "Searching for OTP in plugins..." is simply the last thing the old minute printed, before it jumped to the IOS. It would print that every time independent if defused or a otp.bin is present or valid. The old stroopwafel, when compiled with OTP_IN_MEM simply had a array defined as buffer for the OTP, minute was searching that and if present it would put the OTP data there. The old stroopwafel I had precompiled as release, was compiled with OTP_IN_MEM. That was only required for defuse, because there the real OTP was zerod out, but I wanted my binaries be also defuse compatible, so I left it on.
If it hangs at tha message it simply means the IOS crashed before it could take over the screen output. It doesn't indicate any problem related to the OTP.
In the latest stroopwafel and minute I changed how the OTP gets passed. Now stroopwafel gets a pointer to the OTP store passed through PRSH. If stroopwafel doesn't get this pointer, it just uses the system otp. So minute doesn't need to search anymore for the OTP array. The search and the message with it was removed in this commit: https://github.com/jan-hofmeier/minute_minute/commit/d89484401846326448e4c1262cba26eda0ac4604
The OTP store was removed from stroopwafel, so a old minute wouldn't find anything there: https://github.com/jan-hofmeier/stroopwafel/commit/69eb6ac84af45123d850ddcdfdb3765cc52d29ee

Because either booting a old stroopwafel with a new minute or a new stroopwafel booted on a defused console with an old minute would result in a wrong OTP store, which would damage the file systems, both the new minute and the new stroopwafel check each other for being new enough. If minute detects an old stroopwafel, it would give an error and refuse to boot it. If stroopwafel detects an old minute, it will just hang.

If you boot a new stroopwafel with the old minute it would exactly hang at the message you describe. In the new minute this message was clearly removed.

If you select Retart minute in minute, it will load the fw.img from SD, even if it was loaded from SLC. That is also a way you can make sure you loaded minute from the SD.

The latest minute (at the time of writing) is in the speed-v1.3 release and has the sha256: 4050ce41203060a4040c8a3697fb27a355e05ece97b3eab97bbf91b0cb9eb821

 

[CrazySquid]

@CrazySquid maybe try reinstalling OSv10, in case any of the libraries damaged.

Still the same, however I have new logs... and it seems to fail now with something related to BOSS? This is weird, as I didn't mess with the filesystem at all and both MLC Checker and SLC Checker run without errors... perhaps is related to the Nintendo Network shutdown? I'm not sure...

EDIT:Nevermind, it's fixed!

 

[Splatfest]

When I press B while booting and go into fw_img_loader I get a pink screen then I get stuck in the Wii U menu screen. What can I do?

 

[SDIO]

You need to use the fw_encrypted.img and rename it to fw.img