Files appear on computer but not on clip

I have tried to change my usb selection, and have even reformatted my clip, along with getting the most up to date firmware.  But, for some reason when I transfer songs to my Clip the computer tells me that they are there, and I can even download the songs from the Clip to other computers, but the clip does not recognize them.  I have tried this with mp3 files, wma files and a host of other file types, but they just do not appear on my Clip.

Any suggestions? 

The mp3 files may indeed be there, but the device cannot list them for playback without proper ID3 tags embedded into the files.  If the files are transferred using Windows Media Player, these tags can be generated by the program automatically.

If you right-click on a track or album, you can use the Advanced Tag Editor of Windows Media Player to edit the tags.

A popular editing tool is free, download MP3Tag and add the ID3v2.3 ISO 8859-1 format tags to your music files.  Retransfer them to your Clip, and they can be sorted by Album / Artist / Genre / Song.  If the tags are missing, your music will be listed as “unknown”.