PSP 1004 (6.60) Won't Launch Games from Memory Stick – Fixes

PSP-1000 (model 1004 = North America) on firmware 6.60 (official or CFW) failing to show/run ISOs/CSOs from Memory Stick is common. Check these in order:

1. File Structure (Most Common Fix)

• ISO/CSO must be in ms0:/ISO/ (root of Memory Stick → folder named ISO in caps)
• Not in /PSP/GAME/ (that's for homebrew/EBOOT.PBP)
• Not in subfolders: ms0:/ISO/MyGames/Game.iso → won't show. Must be ms0:/ISO/Game.iso
• Filename: No special chars, ≤ 64 chars, .iso or .cso extension

2. File Integrity

• Corrupted download → re-dump from UMD (if you own) or re-download from trusted source (Redump verified)
• Verify SHA-1/MD5 against Redump.org entry
• CSO compression errors → convert to ISO (UMDGen, ISO Tool)

3. Firmware & CFW Status

• OFW 6.60: Cannot run ISOs natively. Need CFW (Custom Firmware) – PRO-C2 / ME-2.3 / LME-2.3 (permanent or Infinity)
• If CFW installed: Ensure UMD ISO Mode in Recovery Menu / VSH Menu is set to M33 driver or NP9660 (not "Inferno" or "Sony NP9660" for some games)
• Fast Recovery: On 6.60, CFW is often "temporary" – run Fast Recovery app after every cold boot

4. Memory Stick Health

• Fake/counterfeit sticks (common on eBay) report false capacity → corruption. Test with H2testw (Windows) or F3 (Linux/Mac)
• Format FAT32 (32 KB allocation unit) via PC or PSP (Settings → System Settings → Format Memory Stick)
• Try a known-good stick (SanDisk, Sony, 4–32 GB)

5. Game Compatibility

• Some games need Prometheus / ISO Tool patching (e.g., God of War, MGS: Peace Walker)
• Homebrew/PS1 Classics go in /PSP/GAME/ as EBOOT.PBP

Quick Diagnostic Checklist

1. CFW installed? (VSH Menu → System Info → "6.60 PRO-C2" etc.)
2. Fast Recovery run this session?
3. ISO in ms0:/ISO/ root?
4. ISO verified (Redump hash)?
5. Memory Stick genuine & formatted FAT32?
6. UMD ISO Mode = M33 / NP9660?

If all yes and still invisible, try ISO Tool (homebrew) to "Refresh" database. Post on r/PSP or PSX-Place with VSH Menu screenshot for expert help.