My sansa e250R

You need to reformat the device

Format - Erases Everything: Connect your Sansa player to the computer and open Windows Media Player. Click on the Sync tab. Pull down the drop down menu underneath the Sync tab by moving your cursor over the Sync tab and left clicking on the little black arrow underneath the Sync tab. Highlight "Sansa 1GB" (wording may vary slightly), and then select "Format." - this should erase everything.
-Tha Mp3 Doctor

In your windows media you will see the device name listed..you have to make sure the device is under MTP mode..then click on the player and you will see all the songs...you can just right click on the songs and delete them..if you dont want the device to sync automatically you can click on sync and then click on the device name and click on sync setting..there you can modify if you want it to sync automatically..
Should you have any questions..let me know..
P.S.Please rate accordingly...
Thank You
Computerrep

Get software from Sandisk's website

These are the most common methods for recovering Sandisk's Sansa Mp3 Players. I have been almost universally successful in recovering Sansa players using one or a combination of these methods. These methods do not work if you are having synchronization or music format issues - they are for recovering a player that will not power up, freezes, flashes, is not recognized by the computer, and a host of other issues.

Reset the Sansa Player first. On most models, restart is done by holding the power button in for 15 seconds or longer. Check your specific manual to be sure. The manuals are available from the Sansa website if they have been misplaced.
Download the Sansa Recovery Tool from the Sansa website.
Format - Erases Everything: Connect your Sansa player to the computer and open Windows Media Player. Click on the Sync tab. Pull down the drop down menu underneath the Sync tab by moving your cursor over the Sync tab and left clicking on the little black arrow underneath the Sync tab. Highlight "Sansa 1GB" (wording may vary slightly), and then select "Format." - this should erase everything.
Firmware Upgrade- Erases Everything: Get the latest firmware upgrade from Sansa - it updates the firmware and erases every song in the player all at once. Note: this method doesn't work if already have the latest firmware. Go to this website and click "Firmware Updater" to find out: http://www.sandisk.com/DriverDownload/driverList.asp
If these fail, then:
Try this: disconnect the player from the computer, turn it off, hold in the volume + button, and reconnect the player to the computer while holding the volume + button in. Keep holding the volume + button for an additional 5-50 seconds. Windows should eventually go into recovery mode and revive the player- it will pop up a window that says Found New Hardware Wizard.
If you get the problem where MTP Device keeps popping up continuously, uninstall the “MTP Device” by going to Start à Control Panel àSystem à Hardware à Device Manager (you computer may vary slightly, depending on Windows Version).
You may have to restart your computer after each of these methods to get them to work properly. Disconnect your Sansa player BEFORE shutting down your computer.
-Tha Mp3 Doctor

There are a few different ways to delete songs off your player - see especially the method involving the firmware update.
Preventive Medicine: To prevent Windows Media Player from adding all of your My Documents files to the Sansa player every time you connect the Sansa to the computer - Connect your Sansa player to the computer and open Windows Media Player. Click on the Sync tab. Pull down the drop down menu underneath the Sync tab by moving your cursor over the Sync tab and left clicking on the little black arrow underneath the Sync tab. Highlight "Sansa 1GB" (wording may vary slightly), and then select "Set up Sync". When a window pops up, uncheck the box that says "Sync device automatically".
Quick Method 1 - Erases Everything: Connect your Sansa player to the computer and open Windows Media Player. Click on the Sync tab. Pull down the drop down menu underneath the Sync tab by moving your cursor over the Sync tab and left clicking on the little black arrow underneath the Sync tab. Highlight "Sansa 1GB" (wording may vary slightly), and then select "Format." - this should erase everything.
Quick Method 2 - Erases Everything: Get the latest firmware upgrade from Sansa - it updates the firmware and erases every song in the player all at once. Note: this method doesn't work if already have the latest firmware. Go to this website and click "Firmware Updater" to find out: http://www.sandisk.com/Retail/DriverDownloads.aspx
Slow Method, allows more control over what gets deleted: In Windows Media Player 11, the files are organized by Music, Pictures, Videos, Etc. First, you will want to plug the Sansa player into the computer. Then click the Library tab in Windows Media Player. You will most likely be in Music view. You will see two sets of folders in the left-hand side of Windows Media Player. The first set are all the files stored in your computer. The second set of folders underneath the line that says Sansa 1GB Mp3 player (I forget the exact wording) has all the files that are stored in your Sansa player. Click on the "All Songs" folder. You can individually delete all the songs that you want by left-clicking once on the song name in the middle of the Windows Media Player window, and then pressing "Delete" on your computer's keyboard. You will have to repeat this process again for images, videos, etc by clicking the little arrow next to the picture of the musical note on the upper left hand corner of Windows Media Player, and expanding the dropdown menu, and selecting "images"...then "Videos" etc.
NOTE: After plugging in your Sansa player, if you see a message that says "Connect a Device" in the Sync tab on Windows Media Player, then the cmputer is not properly recognizing your Sansa player, and you may need additional instructions from me.
-Tha Mp3 Doctor

There are a few different ways to delete songs off your player.

Preventive Medicine: To prevent Windows Media Player from adding all of your My Documents files to the Sansa player every time you connect the Sansa to the computer - Connect your Sansa player to the computer and open Windows Media Player. Click on the Sync tab. Pull down the drop down menu underneath the Sync tab by moving your cursor over the Sync tab and left clicking on the little black arrow underneath the Sync tab. Highlight "Sansa 1GB" (wording may vary slightly), and then select "Set up Sync". When a window pops up, uncheck the box that says "Sync device automatically".

Quick Method 1 - Erases Everything: Connect your Sansa player to the computer and open Windows Media Player. Click on the Sync tab. Pull down the drop down menu underneath the Sync tab by moving your cursor over the Sync tab and left clicking on the little black arrow underneath the Sync tab. Highlight "Sansa 1GB" (wording may vary slightly), and then select "Format." - this should erase everything.

Quick Method 2 - Erases Everything: Get the latest firmware upgrade from Sansa - it updates the firmware and erases every song in the player all at once. Note: this method doesn't work if already have the latest firmware. Go to this website and click "Firmware Updater" to find out: http://www.sandisk.com/Retail/DriverDownloads.aspx

Slow Method, allows more control over what gets deleted: In Windows Media Player 11, the files are organized by Music, Pictures, Videos, Etc. First, you will want to plug the Sansa player into the computer. Then click the Library tab in Windows Media Player. You will most likely be in Music view. You will see two sets of folders in the left-hand side of Windows Media Player. The first set are all the files stored in your computer. The second set of folders underneath the line that says Sansa 1GB Mp3 player (I forget the exact wording) has all the files that are stored in your Sansa player. Click on the "All Songs" folder. You can individually delete all the songs that you want by left-clicking once on the song name in the middle of the Windows Media Player window, and then pressing "Delete" on your computer's keyboard. You will have to repeat this process again for images, videos, etc by clicking the little arrow next to the picture of the musical note on the upper left hand corner of Windows Media Player, and expanding the dropdown menu, and selecting "images"...then "Videos" etc.
NOTE: After plugging in your Sansa player, if you see a message that says "Connect a Device" in the Sync tab on Windows Media Player, then the cmputer is not properly recognizing your Sansa player, and you may need additional instructions from me.

-Tha Mp3 Doctor

Go ahead and do this, in case the DB is corrupted:
Format - Erases Everything: Connect your Sansa player to the computer and open Windows Media Player. Click on the Sync tab. Pull down the drop down menu underneath the Sync tab by moving your cursor over the Sync tab and left clicking on the little black arrow underneath the Sync tab. Highlight "Sansa 1GB" (wording may vary slightly), and then select "Format." - this should erase everything.
Firmware Upgrade- Erases Everything: Get the latest firmware upgrade from Sansa - it updates the firmware and erases every song in the player all at once. Note: this method doesn't work if already have the latest firmware. Go to this website and click "Firmware Updater" to find out: http://www.sandisk.com/Retail/DriverDownloads.aspx

Try this: disconnect the player from the computer, hold in the volume + button, and reconnect the player to the computer while holding the volume + button in. Keep holding the volume + button for an additional 5-50 seconds. Windows should eventually go into recovery mode and revive the player- it will pop up a window that says Found New Hardware Wizard.
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Download the Sansa Recovery Tool from the Sansa website.
Format - Erases Everything: Connect your Sansa player to the computer and open Windows Media Player. Click on the Sync tab. Pull down the drop down menu underneath the Sync tab by moving your cursor over the Sync tab and left clicking on the little black arrow underneath the Sync tab. Highlight "Sansa 1GB" (wording may vary slightly), and then select "Format." - this should erase everything.
Firmware Upgrade- Erases Everything: Get the latest firmware upgrade from Sansa - it updates the firmware and erases every song in the player all at once. Note: this method doesn't work if already have the latest firmware. Go to this website and click "Firmware Updater" to find out: http://www.sandisk.com/Retail/DriverDownloads.aspx
or
http://www.sandisk.com/DriverDownload/driverList.asp
-Tha Mp3 Doctor

Hi tater. Hmmm. The product category you selected is for a Standard E260. But if your player is an E250R (Rhapsody player), here's a set of procedures that might help you. Deleting songs from your E250R can be done in 2 ways: By using Windows Media Player 10 or 11, or by browsing the player through Windows Explorer. Before you delete files, though, it's important to know that your player comes in 2 modes: "Rhapsody" and "PlaysForSure". The reason why is that music files saved in one mode would not be seen in the other mode, and vice versa. Therefore, if you can't find the music files in your player, switch to the other mode. Here's how to do it: Use the "Menu" button to navigate the player as follows: Menu > Settings > Mode > This will give you the option of: "Rhapsody" and "PlaysForSure". Here's how to delete your songs: (1) By Using WIndows Media Player: > Plug your Sansa to your computer and open your Windows Media Player. > If your Windows Media Player is version 10, then click on the "Sync" tab and you should see your player ("E250R") on the right pane along with its folders, named "Data" and "Media" or "Music". Expand the "Media" folder and you'll see the "Music" folder containing your songs. Right-click on a song and select "Remove" to delete them. > If your Windows Media Player is version 11, then either click on the "Sync" or "Library" tab and you'll see your player listed on the left pane. The music files will be displayed on the center window. Right-click on a song and select "Delete" to delete the songs. (2) By browsing the player in Windows Explorer Note: the folders containing the music files on your player are "Hidden" and you would need to set your Windows Explorer to show "Hidden Files and Folders". Open your Explorer, select "Tools" on the top menu, select "Folder Options", select the "View" tab and enable the "Show Hidden Files and Folders" radio button. > Plug your Sansa to your computer and open your Windows Explorer > If your player is in "PlaysForSure" mode, then your player will be recognized as a "Portable Media Device". Double left-click on your Sansa E250R and you'll see 2 sub-folders named "Data" and "Media". Open the "Media" folder and you'll find sub-folders normally named after the Artist. Your songs are located on those Artist folders. Delete them by using the keyboard "Delete" key or right-click the file and select "Delete" > If your player is in "Rhapsody" mode, then your player will be recognized as a "Removable Drive" with a drive letter. Double left-click on your Sansa E250R and you'll see the following sub-folders: "Albums", "Music", "Photo", "Pictures", "Playlist", etc. Your songs can be found in the "Music" sub-folder. Delete them by using the keyboard "Delete" key or right-click the file and select "Delete" I hope this procedure helps. A bit lengthy but, hey, it worked for me (lol).

Use Windows Media Player

Use Media Monkey instead, or change Windows Media Player's configuration, so that it sees more songs.