Use Mcd001.ps2 for your primary saves and Mcd002.ps2 for backups or secondary games.

It stores saved game data (save states) for the second slot.

Keep the .ps2 files directly in the memcards folder to avoid detection issues.

Most "Mcd002.ps2 download" links online are either unnecessary or potentially unsafe. You can easily create a fresh, clean memory card file directly within PCSX2 :

Are you trying to or looking for a specific game save ?

Right-click the newly created card and select . Where to Find the File on Your Computer