You must create a file named keys.txt (it must be .txt and not .txt.txt ).
key.txt follows a simple key_name = key_value format, where each line represents one key. Keys are represented as hexadecimal strings (64 characters for 256-bit keys, 32 characters for 128-bit keys).
Wii U retail discs and digital eShop games are protected by proprietary Nintendo encryption. To legally play these games on an emulator, Cemu needs specific cryptographic keys to unlock the data.
A universal master key used by the Wii U console system. Cemu requires this to understand the base encryption layer of the console.
If using .wux or .wud , double-check that your keys match the specific region of your game dump.
Attempt to load a Wii U game to see if Cemu can now decrypt and run it using the provided keytxt.
was the master code, a single hex string required to let Cemu understand the console’s basic language. Title Keys
Run the homebrew application XYZZY on your console.
A single space, followed by an optional description or Title ID so you can keep track of which key belongs to which game. For the Common Key:
If Cemu is still not playing your games, consider these troubleshooting steps:
To understand the utility of keys.txt , you must understand how Cemu handles encryption. The Wii U console utilizes a complex set of encryption keys to verify and run software.
Incorrect file location or file extension. Fix:
Depending on your operating system or handheld interface, Cemu expects to look for the file in specific default directories.
If you are building a modern Cemu library using current dumping methods (NAND dumps and .wua files), you do not need keys.txt . However, if you are preserving an older library of extracted .rpx games, keys.txt is a functional, albeit aging, necessity. It gets the job done, but it represents the "old way" of Wii U emulation.
was vital; a key for a European game wouldn’t fit the lock of a North American one. Cemu on Windows - EmuDeck Wiki
: If you have legally dumped your own Wii U games using a homebrew tool like dumpling or wudd , you must extract your own console’s OTP key and title keys from your console. Cemu’s documentation encourages users to dump their own keys from a real Wii U.
The required to decrypt and play packaged Wii U games on the Cemu Emulator. Without this text file properly populated and located, Cemu will trigger a "Could not decrypt title" error.