If you want to boot into the DSi Home Menu rather than launching a game directly, a valid NAND is required.
Titles like Zelda: Four Swords Anniversary Edition or Flipnote Studio must be "installed" to a virtual NAND to run.
Setting up the NAND involves linking the file within the emulator's configuration. For PC (Windows/Linux/Mac): nandbin melonds
In the world of Nintendo DS emulation, is the critical file representing the console's internal flash storage. For melonDS , this file is the backbone of advanced features, particularly for those looking to emulate the Nintendo DSi and its library of DSiWare. What is nand.bin?
Digital games and applications installed directly to the console. If you want to boot into the DSi
The nand.bin file is a raw dump of the DS or DSi's on-board NAND flash memory. Unlike standard game ROMs (which contain game data) or BIOS files (which contain boot instructions), the NAND stores:
Authentic system behavior, such as calendar alerts or system-level settings, relies on the data stored in this file. How to Set Up nand.bin in melonDS For PC (Windows/Linux/Mac): In the world of Nintendo
Complete Guide to nand.bin in melonDS: Setup and DSi Emulation
User profiles, birthdays, and favorite colors. Firmware Data: The actual operating system environment.
Specifically for DSi systems, where save data for digital titles is stored within the NAND rather than on a cartridge. Why You Need nand.bin for melonDS