Things You'll Need
Instructions
Downgrade Solution
Download 500.PBP and 5.00 m33-6 files on your personal computer from a PSP home-brew website such as PSP Slim Hacks or Quickjump Gaming Network.
Connect the PSP USB cable to your PSP system while the power is on. Click on the option to connect via USB when it shows up on the PSP screen.
Insert the other end of the PSP USB cable into your PC. When the device is recognized, click on "Open folder to view files."
Navigate to the X:/PSP folder on your PC using your mouse.
Extract the 5.00 m33-6 installer files on your PC using a software compression tool such as Winrar or Winzip. It is best to extract them directly to the desktop for ease of use.
Copy the Update folder from the install files on your PC to the X:/PSP/GAME/ folder on your PSP by dragging and dropping the folder on the appropriate subdirectory on your PSP.
Extract the 500.PBP file from the downloaded archive. If the extracted file is labeled EBOOT.PBP, right-click on the file and rename it 500.PBP.
Copy the 500.PBP to the X:/PSP/GAME/UPDATE directory. When it finishes, unplug the USB cable from the PSP and computer.
Navigate to the PSP memory stick directory with your PSP's directional pad. Select "5.00 UPDATE" from the Game menu. Wait for the installation to complete before proceeding.
Load each game that was experiencing issues with save file corruption problems and check to see if you can load them with the new firmware installation.
Gen-D3 Upgrade Solution
Download 5.50 GEN-D3 (v.2) and 5.50 GEN D2-D3 switcher installer files on your personal computer from a PSP home-brew website such as PSP Slim Hacks or Quickjump Gaming Network. It is important to make sure to get version 2; the original version has bugs that can make your problems worse.
Insert the PSP USB cable to your PSP system while it is powered up.
Extract the 5.50 GEN-D3 and 5.50 GEN D2-D3 switcher installer files on your PC's desktop.
Insert the other end of the PSP USB cable into your PC. When the device is recognized, click on "Open folder to view files."
Copy the Update folder from the install files to the X:/PSP/GAME/UPDATE folder on your PSP and copy the 5.50 GEN D2-D3 switcher files to your X:/ directory.
Disconnect the USB cable from both the PC and PSP when the transfers are complete.
Select "5.50 UPDATE" from under the PSP Game menu. Wait for the installation to finish before proceeding.
Reset your PSP console. An option should come up to boot in either 5.50 GEN-D2 or 5.50 GEN-D3. Use the directional pad to select the version you wish to load, then click the "X" button to proceed.
Test the files by selecting each version of the firmware to attempt loading the game and loading the save files. One should work to load your saves.