PSP Hard Drive Problem

Today I was copying a movie to my PSP when I saw a very strange problem.

I was deleting a few images to make room for the movie and after I deleted them all ( this was all on my MAC ) I noticed that the occupied hard drive was still the same! So I started deleting all the pictures and when it was fully empty, the hard drive was still the same!

After I searched for a while a link drove me to the Ubuntu Forums where one person was having the same problem.
After a few replies a guy suggested to clean the trash of the Linux OS it self and has you all know the MAC OS core is the same has Linux ( the Kernel )
So, I cleaned the trash can and for my surprise now the hard drive space was correct!

It is very strange, why and how the heck would the PSP start searching for files in the computer and then start treating them as it's own?
Well, don't ask me! Anyway, that's the solution.

This does only happen in MAC and Linux's, Windows is completely fine. The best solution too solve this issue is to find some sort of PSP Manager application.