You generally cannot use a USA save file ( ULUS... ) on a European game ISO ( ULES... ). The PSP will usually tell you the data is "corrupt" if the IDs do not match. Ensure you download the save file that corresponds to your game's region.
For a 100% complete save file for Naruto: Ultimate Ninja Heroes 2: The Phantom Fortress savedata de naruto ultimate ninja heroes 2 psp
This save data file for Naruto Shippūden: Ultimate Ninja Heroes 2 (also known as Naruto Ultimate Ninja Heroes 2 in some regions) unlocks most of the game’s content, allowing you to jump straight into the action without grinding through the story mode or farming support points. You generally cannot use a USA save file ( ULUS
Before overwriting with a downloaded save data, copy your original folder to your PC. That way, you can always go back if something goes wrong. The PSP will usually tell you the data
If you are transferring or downloading save data, ensure it matches your game's region (NTSC/USA, PAL/Europe, or JP), as files from different regions are generally incompatible. Save Data Directory