hi,
you should reinstall the firmware in the mp3 player to do that you can go on the mp3 manufacture's website click on support and look for the appropriate firmware that fit your model number once it's download plug your mp3 to your pc and then run the firmware updater you should be able to use your mp3 good luck
hi i too had the same problem and i clean it up by formating the memory card this is alone the way to clear it and it comes becasue of virus and full memory so just keep ur memory little free