I was listening to my c150 last night and the battery died. I thought, no problem, I’ll just put another one in. I replaced the battery, but when I turned it on, it was stuck on the SanDisk screen for almost a minute. It played some songs from the album I was listening to, but when I go through the menu, it lists all of my music as unknown and under the file WMPInfo.xml. ll of songs still work when I played them through my laptop, but they won’t even show up on the player itself.