Messed up HDD

[CaptainHIT]

Lately I was copying over Genesis/MD roms to my HDD from a USB stick. I've created a "Genesis" drawer in the "boot" dir because PGEN 1.5.1 is seeing just this dir on the HDD. I used GoodGEN renamed roms (they have long names etc) so I have e quite good look on what I own. I've got an old 256MB flash pen which I use for transferring and as you can understand it get's filled up quite quick with many roms, so I used it several times to copy over what I have. Then after a while uLaunch started to freeze while copying. I have waited more than 10 minutes in thoughts it could continue, but nope, it wasn't. I had to reset my PS2 to regain control of it. Then I tried to copy over what was left on the flash pen but it freezed right after the 3rd file again. I tried this several times and it happened always after the 2nd or 3rd file. I remembered the old FAT filesystem which doesn't like more than 255 files in a single dir, so I thought it could be the same, so I created a few directories in the "Genesis" drawer and cut&pasted roms inside them.
But then I started to get an HDD error, I couldn't read the dirs or the files. Even PGEN couldn't load the roms from my "Genesis" dir or any dir inside it. What could have happened? Any idea how to fix this? Do I have to reformat the HDD?
Thanks in advance for all suggestions.

[spkleader]

CaptainHIT: I guess your only try .
is to take the hdd out, plug into the PC and use a program called WinHiip.
If there's a problem with your hdd structure it will try to fix it. (a logical error)
If there's a problem with your hdd hardware, then you're pretty much screwed (a physical error)
But give winhiip a try. Just google for it.. it's easy to find.
Good luck!