My sansa player doesnt trun on. but if i join it to the usb or charger it turns on. and the battery is also full. and as soon as i remove the cable it goes off again. i tried everything. but didnt work, please help me with this..

You can try and reset the player. resetting a Clip player: 1. Slide and hold the Power switch up for approximately 20 seconds. 2. Release the Power switch. 3. To turn the player on, slide the Power switch up then release instantly.
Some things to check for when your player does not act like its taking a charge.
USB Cable Make sure that the USB cable is properly plugged in and use the original cable that came with your player.
Computer in Hibernation mode Make sure the computer isn't entering hibernation or sleep mode while the device is connected. The computer must be ON in order to charge your player.
USB Port 2.0 Make sure the player is connected to a USB 2.0 port (1.1 occasionally causes charging problems).
USB Port location Try plugging into different USB ports (i.e. USB port in the back of the computer); occasionally the front USB ports have limited power to charge up the device.
Battery Make sure the battery is fully charged. It takes approximately 3 hours to fully charge the battery.
Latest firmware Depending on what Sansa player you have, make sure it's up to date with the latest firmware.
AC charger (optional) AC chargers (sold separately) have a 500-1000 milliamp max output, which provides much better charging ability than a USB port.
I have some tips posted here on MP3 players and their problems. Connection problems MP3 player not found by computer
SanDisk Mp3 Player Frozen

Plug one end of the supplied cable into the bottom of the Sansa, with the Sansa logo on the cable facing up. Plug the other end of the cable into a computer's USB port or a USB charger (such as you might have for your cell phone). If the Sansa is charging, you'll see the battery gauge cycle from right to left.

USB Cable Make sure that the USB cable is properly plugged in and use the original cable that came with your player. Try a USB plug o the back of the computer. These plugs have more power available.
Computer in Hibernation mode Make sure the computer isn't entering hibernation or sleep mode while the device is connected. The computer must be ON in order to charge your player. Check you screensaver and power settings.
USB Port 2.0 Make sure the player is connected to a USB 2.0 port (1.1 occasionally causes charging problems).
Battery Make sure the battery is fully charged. It takes approximately 3 hours to fully charge the battery.
Latest firmware Depending on what Sansa player you have, make sure it's up to date with the latest firmware.
AC charger (optional) AC chargers (sold separately) have a 500-1000 milliamp max output, which provides much better charging ability than a USB port. These accessories are available on our online store.
Next try and reset the player. Resetting the player: 1. Slide and hold the Power switch up for approximately 20 seconds. 2. Release the Power switch. 3. To turn the player on, slide the Power switch up then release instantly.
Once it is back working, go to the SanDisk support site and get the updater program and update your firmware.

If the USB end of the Sansa cable connects to the charger, then there's no problem.

Below are some things to check for when your Sansa player does not charge..
USB Cable Make sure that the USB cable is properly plugged in and use the original cable that came with your player. Also try ports on the back of your computer, these ports have more available power. Some computers have limited power to charge up the device...
Computer in Hibernation mode Make sure the computer isn't entering hibernation or sleep mode while the device is connected. The computer must be ON in order to charge your player.
USB Port 2.0 Make sure the player is connected to a USB 2.0 port (1.1 occasionally causes charging problems).
Battery Make sure the battery is fully charged. It takes approximately 3 hours to fully charge the battery.
Latest firmware Depending on what Sansa player you have, make sure it's up to date with the latest firmware.
AC charger (optional) AC chargers (sold separately) have a 500-1000 milliamp max output, which provides much better charging ability than a USB port. These accessories are available on our online store.

Below are some things to check for when charging your Sansa player:
USB Cable Make sure that the USB cable is properly plugged in and use the original cable that came with your player. Make sure the computer isn't entering hibernation or sleep mode while the device is connected. The computer must be ON in order to charge your player. USB Port 2.0 Make sure the player is connected to a USB 2.0 port (1.1 occasionally causes charging problems). USB Port location Try plugging into different USB ports (i.e. USB port in the back of the computer); occasionally the front USB ports have limited power to charge up the device. Battery Make sure the battery is fully charged. It takes approximately 3 hours to fully charge the battery. Latest firmware Depending on what Sansa player you have, make sure it's up to date with the latest firmware. AC charger (optional) AC chargers (sold separately) have a 500-1000 milliamp max output, which provides much better charging ability than a USB port. These accessories are available on our online store.
To Remove the Battery... 1. Remove the back on the e200 by removing the 4 screws. 2. Lift off the back by using a finger nail or a small flat head screw driver. It will not take a lot of force to remove. NOTE: When replacing the e200 battery be sure that the contacts on the battery line up with the contacts on the player. 3. The battery has three gold contacts on one end of the battery, which is near the words SanDisk Sansa. Be sure these contacts match up with the three gold contacts on the back of the player. 4. Lightly push the lined up battery up against the contacts of the player until the bottom end of the battery can be pushed into place. 5. Replace the lid to the back of the player and then plug the player into the computer using the Sansa cable. 6. Once the player has connected to the computer and is ready to be used or says "Connected", unplug the device.
NOTE: If the device goes directly to a black screen after unplugging it, then the battery has been replaced incorrectly. Take the back off the player once again and flip the battery around and the e200 device should work properly.

It's likely your battery is flat. These devices are designed to run only from their internal battery. If the battery is flat, it won't turn on. To charge the battery connect your charging source (USB port or wall charger). Turn the player on with the mechanical swich. Next hold down the play button for more than 4 seconds. The player will turn off and begin to charge. After about 6 hrs the battery will be full and you can use the player.

Remove the battery, for 1 min, install battery, plug it into a USB cable to the computer

Some USB ports cannot supply enough power to charge the Fuze. I had the same problem. I worked around it by getting a wall charger from RadioShack.

hi ya, ok one of the solution is checking out the trouble of litium battery, i guess has been out of base, i had the same siptom with sansa e250r 2-g, put in right the battery. In back of sansa there are 4 screws that u have to loose it