| Attribute | Details |
|-----------|---------|
| File extension | .ps2 |
| Typical size | 8 MB to 64 MB (configurable in PCSX2) |
| Internal format | Raw or folder-based (PCSX2 proprietary) |
| Can you play it? | No – it must be used with a game ISO. |
| Can you open it? | Yes, using PCSX2's memory card manager or third-party tools like myMC. |
The name Mcd001.ps2 is derived from the PlayStation 2’s file structure. The PS2 used Memory Cards formatted with a file system where system files often ended in .ps2. The "Mcd" prefix typically referred to Memory Card data.
However, in the context of the modding community, this specific file is most famously the anchor for the PS2 PS1 Emulator Swap Trick.
For years, the PlayStation 2 was known for backward compatibility—it could play original PlayStation 1 (PS1) discs natively. But what if you wanted to play a game you downloaded? Or a rare title you couldn't afford? The PS2 security measures were notoriously difficult to bypass via simple burning methods for PS1 games. While PS2 "backup" solutions (like Swap Magic) flourished, PS1 burning remained a stubborn hurdle.
Enter the exploit. By using a specialized disc—often a "Gameshark," "Action Replay," or a dedicated homebrew ISO—users could trigger a memory card exploit. The console would read the legitimate disc, load the exploit code (often saving or reading data to a file named Mcd001.ps2 on the memory card), and then wait for the user to swap the disc. When the user swapped in a burned PS1 game, the console, blinded by the exploit, accepted it as authentic.
If you already have an Mcd001.ps2 file (perhaps downloaded by accident), here is how to use it properly within the PCSX2 emulator.
If you have attempted to use an Mcd001.ps2 file as a “full game” and failed, you likely saw one of these errors:
| Error Message | What It Actually Means | The Fix |
| :--- | :--- | :--- |
| “Not a valid PS2 memory card file” | The file is corrupted or was created for a different emulator. | Delete the file and let PCSX2 create a new one (Config > Memory Cards > New). |
| “Mcd001.ps2 is not a CD/DVD image” | You tried to run the memory card via “Run ISO.” | Go to CDVD > Iso Selector > Browse and select an actual .iso game file. |
| “No save data found for this title” | The Mcd001.ps2 file contains saves for other games, not the one you are playing. | Start a new game; the emulator will save to the card automatically. |
While we do not condone piracy, these communities provide excellent guidance on dumping your own games:
