Help i just bought a sansa e250 without any of the cords or anything, and i just got the usb and charger for it from walmart and it's been charging for 4 hours and i took it off the charge and it just says 'battery too low system shutdown" so i'm not sure what i need to do now to make it charge up.

you probably fried the entire thing. Using the wrong power cord is a big no no as the voltage and amplitude must match or you could easily overload or slug down the product. Sorry but the best advice is learn from the mistake and use the thing for parts as that would void manufacturers warranty.

I believe the cable is the charger. I have an e250 which charges from the computer. Simply connect the player to the computer using the cable, and when the player is detected by the computer - it is charging!

My friend have a different charger though, but she bought it from the store.

Down load the firmware on Sansa's website. I have a Sansa 250R and it wouldn't work with the new replacement usb (Griffin) cord I bought at Best Buy. So I bought a Sansa Fuze and the cord that came with it worked on the E250R. Huh? Yeah, go figure...and oh, that replacement Griffin usb cord I bought worked fine with the new Fuze. I came real close to buying a new battery for the E250R but instead invested that money in the Fuze.

when i turn my mp3 "on" then it will refreshered and the screen will turn black it will not display anything what should i do, and it is not charging too.

is there a charger (cord plugged into the base) plugged in?

my sansa e250 wont turn on only when i plug it into the charger...and when i try to turn it on without plugging it into the charger it says battery is low and turns off..when actually the battery is full...?

Get a USB wall charger - one end plugs into the wall, and it contains a USB port. Readily available from Walmart, Target, etc. I would recommend the Sansa specific one, available at become.com:
USB Ac Charger Sandisk MP3 The Macally USB AC charger is a USB power adapter you can use to charge your Sansa MP3 Player at home, on the road, or whenever your Sansa is not ... Read More

$18.99 - $19.99 at 3 stores

My son has an 8GB Sansa View and his USB cords and wall chargers work with my Sansa e250.

what have happened? did it just stop work or
have u done anything or dropt it? i need more information if i gonna try to help ;p

That has never happened to me before, but it would be nice.