Getting error message that says File System Err,,,music won't play

WOW, It worked! This is great. I bought a shoe-box full of MP3 players at the swap for $5. Well over 100. This same action fixed several different brands and sizes of player. Well, there was one BRAND NAME player that will NOT respond. If it were just one I'd say it was a fluke. 36 Apple products. 22 of them worked. 5 are scrap and the other 9 seem fine but won't go past powering up and will not respond to the FIX. Any other ideas for the APPLES? Don't even say it, lol.... Out of 30+ units of NON- I Pods all but one have worked. There is way over 100 here, maybe closer to 3?? Well i have a lot of work to do. THANKS! WOW, It worked! This is great. I bought a shoe-box full of MP3 players at the swap for $5. Well over 100. This same action fixed several different brands and sizes of player. Well, there was one BRAND NAME player that will NOT respond. If it were just one I'd say it was a fluke. 36 Apple products. 22 of them worked. 5 are scrap and the other 9 seem fine but won't go past powering up and will not respond to the FIX. Any other ideas for the APPLES? Don't even say it, lol.... Out of 30+ units of NON- I Pods all but one have worked. There is way over 100 here, maybe closer to 3?? Well i have a lot of work to do. THANKS!