I tried to put a couple of songs on my car Mp3 player today but when i play it in the car, it will only display the track info and won't sing, i took it back to my computer to check for any error, i discovered if I play a track from "My Music" folder it will play but when i copy the same track to the Car Mp3 folder and play it, Window Media Player will pop up a dialogue box and say:

                                                             The file you are attempting to play has an extension (.mp3) that does
                                                             not match the file format. Playing the file may result in unexpected
                                                             behaviour.

                                                             Do you want the player to play this content?

What could be the problem?

change file format to wma

Don't copy and paste tracks to your mp3 player,sync it with the media player on your pc.
You might need to format the player if the above suggestion doesn't work.

Thanks guys I'ma try it out soon!