Introduction

If you find a .zip or .cso file labeled "Resident Evil 4 PSP," it usually falls into one of three categories:

  1. Install Custom Firmware: You need a hacked PSP (e.g., PRO-C or LME).
  2. Locate a PS1 EBOOT: Search for a Resident Evil PS1 game (Director’s Cut or RE2/RE3). These work flawlessly.
  3. Understand the Folder Structure: On your PSP’s memory card, navigate to /PSP/GAME/. Create a folder called RESIDENT_EVIL_4 (fake).
  4. The ISO/CSO Placeholder: For real PSP games, you put ISO files in the /ISO/ folder. For PS1 classics, the disc is converted to EBOOT.PBP.
  5. The .zip extraction: Download Resident_Evil_4_Psp.zip, extract it using WinRAR or 7-Zip. If you see a UMD_DATA.BIN file, you have a fake file. If you see EBOOT.PBP, you might have a PS1 game or mobile port.

Red Flags to watch for: