No room on mp3 player when there aren't any files on it??? Please help!

I’ve had a silver 8gb fuze for about a month, and everythings been working fine. But then I went to play my music and there was nothing there. I checked it on the computer, and it says that there are like 23 mb remaining on the device, but I can’t find any files. I deleted all the empty folders and tried to add the music back, but it said there was no room. The devIcon.fil thing is still there, but that’s the only thing that hasn’t been deleted. 

I also have a 16gm micro sdhc card and all the files are ok on that. They’ll play, and the ones that were there in the first place didn’t get wiped out. Oh, and I haven’t changed the usb mode, so I’m pretty sure that has nothing to do with it. Any help would be greatly appriciated. Thanks in advance!