Sharper Image mp3 2 gig

I am helping a friend with her Sharper Image mp3/video player 2 gig. She does not have a computer so I put her music on it for her. Never had a problem in the past with my old computer (windows XP). Now I am having troulbe putting music on it with my new computer (Vista). The mp3 player says it is empty, when I hook it up to my computer it says there are no files, but when I go to properties its says that 1.33GB are used out of 2GB. There should be at least 4 folders (music, movie, book, record). Windows Media player says it has a while synchronizing. I am tempted to format it, but don't if that will solve it or just make it worse. Thanks in advance.