i read this thread and downloaded the program in it but the ploblem still present " file format error "
First off, have you formatted your player? See
How to Remove a Memory Hack. Format errors are common on hacked players.
The hacked memory tricks your computer into showing the false memory and allows you to "download" songs or videos to it. What it's really doing is only writing part of the file or it's a ghost file. Then when you try to play it, it shows up Format Error.
I know this isn't what you want to hear, but there is a possibility your player is hacked especially if you bought it off of eBay.