Help my mp3 says disk error and I need help it won't let me do anything

It kind of depends on Which mp3 player you have.

Disk error could mean a bad sector on the disk, that you should be able to fix by wiping it (from your pc) and starting again.
It could also be physical damage, that means the drive is broken and needs to be replaced.

Sepa la chingada waat kind is mine so that really didn't help