Things You'll Need
Instructions
Turn your Sony PSP on by sliding the power button up. Connect your USB cable to the PSP and navigate to the "USB Connection" option in the PSP's settings menu. This will connect your PSP to your PC. An autoplay window will appear. Select "Browse Files and Folders."
Open your "Recycle Bin" by double-clicking on the recycle bin icon. Locate your deleted PSP files in the recycle bin and right click them. There will be a few options here, but all you need to do is select "Restore Items." The deleted files will now be placed back onto the PSP, thus restoring them completely at their original place.
Navigate to the PSP files ystem and make sure the files were completely restored properly. After verification, disconnect your PSP from your PC and you are done.