I am having the same problem, my Sansa e260 would not charge the battery. I purchased a new battery and the unit worker great again until I tried to charge the new battery. After trying to charge the new battery the unit dies as soon as I unplug the charger, just like it did with the old battery. To me it appears to be a problem with the player and not with the battery.
So far I have not found a solution. My $15 Samsung Galaxy Centura smart phone has replaced my Sansa e260 MP3 player.
