BAD TRACK FOR EVERY SONG
Getting a "Bad Track" message on the E250 may be an indication of memory corruption, music file corruption, or outdated subscription/license info.
One solution would be to format your player in Windows Media Player (version 10 or 11):
1. Make sure your player is in MTP mode by navigating the menu as follows:
Menu > Settings > USB Mode
You would get a choice of "MTP" or "MSC". Please select "MTP". If your player is an "E250 Rhapsody series" player, select "Plays for Sure".
2. Plug your player to your PC and run Windows Media Player. Click on the "Sync" tab and make sure the E250 is listed. Look for the "Format" button (it would look like a "pencil" on Windows Media Player 10) and click on it. Follow the on-screen prompt.
3. Re-load your songs by either copying/pasting your songs to the player or by using Windows Media Player's "Synchronization" feature.
You could also format the player while in "MSC" or "Rhapsody" mode by browsing the player in Explorer, right-clicking the drive letter corresponding to the player, then select "Format". Follow the on-screen prompts
Another solution would be to update the firmware of your player by downloading the Sansa Firmware Updater using this link from the SanDisk website (instructions are found on this site as well):
For standard E250 or E250R "Rhapsody Series":
Make sure your player is set to MSC mode, or "Rhapsody" Mode
The type of music file might also be the cause. If your music files are licensed, purchased or acquired via subscription, you may want to contact the provider for more info on how to re-download the music files.
I hope this helps. There are other procedures available but these might actually make your player work normally again.
Hoping for the best :)