Try: If you have TuneUp Utilities or such, uninstall Xploder, run a registry scan, if errors, fix them, re install, should be fine now.
Also check if you have your .sfi files in you PSP/Movies/Music folders as well.
---------- Post added at 11:14 PM ---------- Previous post was at 11:11 PM ----------
I am not too sure on what .sfi files are. Assuming images/music of some sort owned by Sony. Anyways, a simple try could be also, if you have say My PSP Gamesaves.sfi, just try coping it over, and renaming. I don't think it could be that simple, but worth a try.