A wav file is kind of music file. It's quite unlikely this is one that is so critical for it, that it refuses to play anything else.
Most mp3-players I know have the option to put a file on them from your PC, after connecting with a USB-cable. So find the right cable, the right file and put it in the right place. You might need the right program also.
Kees
i've deleted a wav file off my mp3 and it's saying no files and it won't do anything? i need help. can i put a wav file back on it,so i can record music and listen to it?

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