Even with the file in place, things can go wrong. Here are the fixes for the most common problems.
This is the most sensitive part of the discussion. Because nand.bin contains copyrighted Nintendo code and console-unique encryption keys, we cannot provide direct download links. Distributing nand.bin without permission is illegal in most jurisdictions.
However, you have two perfectly legal options: nand.bin melonds
Place nand.bin inside the melonDS folder (or any folder you prefer).
Launch melonDS → Config → Emu Settings → DSi tab. Even with the file in place, things can go wrong
Enable “Enable DSi mode”.
Under “DSi NAND image”, browse and select your nand.bin file. Place nand
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