If you could find anything on it, try to re-flash the firmware on the mp3 player... custom, the same, or upgrading, doesn't matter... also, google rockbox, its custom mp3 player software, which has way more customization and flexibility than what you come with
EDIT: I found on the rockbox website instructions to recover your sansa, pretty much no matter how badly you screw it up... some of it may be a little hard to follow if you do not have alot of experience. Most likely following the Restoring your firmware under Recovery Mode should be all you need, and could be easily done with windows and your USB cord...
http://www.rockbox.org/twiki/bin/vie...nsaE200Unbrick
Best of Luck!