Keep required BIOS zipped files (like neogeo.zip ) in the same folder as your game ROMs.

This comprehensive guide covers everything you need to know about MAME 0.72 repacks, their compatibility, and how to get them running seamlessly. What is a MAME 0.72 ROMs Repack?

Never unzip your MAME ROMs. The emulator reads the .zip or .7z files directly to locate the necessary game data. Unzipping the files will often cause the game to fail to load.

What or device are you installing these ROMs on?