Windows often hides file extensions by default. You might think your file is named aes_keys.txt , but it is actually named aes_keys.txt.txt . Open File Explorer. Click the View tab. Check the box for File name extensions .
However, if you are using .cia files, these usually need to be "installed" into the emulator first.
Nintendo 3DS software is encrypted. To play these games on an emulator or decrypt them for modding, you need the "Seed" or "AES Keys" that the original hardware uses to read the data. Since these keys are copyrighted material, they aren't included with emulators. You have to provide them yourself in a simple text format. 1. Ensure Correct File Placement