Important legal disclaimer: You must own a physical Nintendo 3DS console to legally dump your own keys. Distributing copyrighted keys is illegal. This guide explains the process, not where to find pre-made files.
The search term aeskeystxt (missing the underscore) is a common typo. The correct filename is aes_keys.txt . However, the emulation community understands both variations. Citra is case-sensitive regarding the content of the keys, but the filename itself is standard. aeskeystxt citra portable
Never use rich text editors. aes_keys.txt must be plain text. Using Word adds invisible formatting characters that break the keys. Use Notepad, VS Code, or Notepad++. Important legal disclaimer: You must own a physical