Need to set device to MTP mode

Not true!!! The Sansa Clip is actually the best mp3 player I have found for listing to audiobooks. Here is what you need to do. Download the latest firmware update on the Sandisk website. You must do this or it just won't work unless you are downloading books from Audible.

I use the Overdrive Media Console and download mp3 and WMA books from my state library. When you hit transfer, be sure it hit advanced options. Browse until you select the audiobook folder on your player. Then transfer to that.

The player will bookmark your last place on anything that is in your audiobook folder. You can easily switch back and forth between your music and book without losing your place! Love it!

It even has a sleep timer on it. I'm in heaven.

You need to check your player for MTP and / Or MSC modes. To use MSC or MTP modes go to your players settings look for USB or Modes.
For a better explanation of these modes of use check out my tip posted here. -->
http://www.fixya.com/support/r3774047-solve_mp3_player_connection_problem <--
copy the address into a new window.

Just to be clear,most players require no special drivers. MSC mode will work out of the box with just about any MP3 player and any OS (W*ndows Linux). MTP mode will work as long as you have WMP 10 or 11 installed. Firstly, I will try to explain MSC mode and MTP mode and what they mean. MSC stands for Mass Storage Class. When your player is in this mode, the computer will see it the same way it would see a Thumb drive or flash drive, as a removable disk. It will assign the first available drive letter to your device, as well as one for the memory card (if it uses one and it is installed). This is probably the more popular of the 2 modes, and is a more "open source" type of standard. Most computers detect the player in this mode without a problem very well and right away.
MTP stands for Media Transfer Protocol. It is a Microsoft standard and is Microsoft's solution to connecting MP3 players and cameras to a w*ndow based Computer. MTP mode must be used in order to transfer ANY Digital Rights Management (DRM) protected content. MP3's downloaded form services like Rhapsody and Napster will only function in this MTP mode.
Most good MP3 players will have both of these modes at the users options.
Although not all do, so it is a good idea to check yours for these settings if you are having connection problems
NOTE: Any songs added to your player in MSC mode will not be available in MTP mode and vise-a-versa. In other words You can't see the files added in the other mode and you can not play them. You know you have some files on your player and can not find them now, you may have to change modes so they are available. Some players in the SanDisk line up use Instead, an "Auto Detect" function that is suppose to Automaticly use MTP mode. If MTP mode does not work for any reason, it should default to MSC mode.
To use MSC or MTP modes go to your players settings.
These settings will vary based on player model and you might have to refer to your users Manual. Check their web site for a download in PDF form. Turn the player on, if it is not already Navigate to the main menu of your player; this is the same menu that gives us options such as Play, Record, Info, etc... Navigate to "Settings" on the main menu of the player. After navigating to "Settings", you should see an option that states "USB" or "USB MODE" From here we can select MSC or MTP modes (could vary based on player model) Highlight the desired mode and select it, at this point it will roll back to the 'Settings' menu Connect the player to your computer and verify it is connecting in the desired mode. It should be noted, when a device is in MSC mode, it will appear as a "Removable disk". When connected in MTP mode, it will show up as an "Audio Device".
Now most players now days can and will use`MS W*ndows Media Player. You can also try to reinstall W*ndows Media Player 10 or 11 Next W*ndows has a update to fix if all else fails try this link. http://www.microsoft.com/downloads/details.aspx?FamilyId=A2E73160-E862-4F19-BB26-C0CAFE798955&displaylang=en

Just to be clear,most players require no special drivers. MSC mode will work out of the box with just about any MP3 player and any OS (W*ndows Linux). MTP mode will work as long as you have WMP 10 or 11 installed. Firstly, I will try to explain MSC mode and MTP mode and what they mean. MSC stands for Mass Storage Class. When your player is in this mode, the computer will see it the same way it would see a Thumb drive or flash drive, as a removable disk. It will assign the first available drive letter to your device, as well as one for the memory card (if it uses one and it is installed). This is probably the more popular of the 2 modes, and is a more "open source" type of standard. Most computers detect the player in this mode without a problem very well and right away.
MTP stands for Media Transfer Protocol. It is a Microsoft standard and is Microsoft's solution to connecting MP3 players and cameras to a w*ndow based Computer. MTP mode must be used in order to transfer ANY Digital Rights Management (DRM) protected content. MP3's downloaded form services like Rhapsody and Napster will only function in this MTP mode.
Most good MP3 players will have both of these modes at the users options.
Although not all do, so it is a good idea to check yours for these settings if you are having connection problems
NOTE: Any songs added to your player in MSC mode will not be available in MTP mode and vise-a-versa. In other words You can't see the files added in the other mode and you can not play them. You know you have some files on your player and can not find them now, you may have to change modes so they are available. Some players in the SanDisk line up use Instead, an "Auto Detect" function that is suppose to Automaticly use MTP mode. If MTP mode does not work for any reason, it should default to MSC mode.
To use MSC or MTP modes go to your players settings.
These settings will vary based on player model and you might have to refer to your users Manual. Check their web site for a download in PDF form. Turn the player on, if it is not already Navigate to the main menu of your player; this is the same menu that gives us options such as Play, Record, Info, etc... Navigate to "Settings" on the main menu of the player. After navigating to "Settings", you should see an option that states "USB" or "USB MODE" From here we can select MSC or MTP modes (could vary based on player model) Highlight the desired mode and select it, at this point it will roll back to the 'Settings' menu Connect the player to your computer and verify it is connecting in the desired mode. It should be noted, when a device is in MSC mode, it will appear as a "Removable disk". When connected in MTP mode, it will show up as an "Audio Device".
Now most players now days can and will use`MS W*ndows Media Player. You can also try to reinstall W*ndows Media Player 10 or 11 Next W*ndows has a update to fix if all else fails try this link. http://www.microsoft.com/downloads/details.aspx?FamilyId=A2E73160-E862-4F19-BB26-C0CAFE798955&displaylang=en

If the book was purchased from the net and came with a license, you will have to set the player to MTP mode and sync the book through Media player or QuickTime. MTP stands forMedia Transfer Protocol. It is a Microsoft standard and is Microsoft's solution to connecting MP3 players and cameras to a w*ndow based Computer. MTP mode must be used in order to transfer ANY Digital Rights Management, (DRM) or protected content. MP3's downloaded form services like Rhapsody and Napster even Amazon will only function in this MTP mode. Now, Any songs added to your player in MSC mode will not be available in MTP mode and vise-a-versa. In other words You can't see the files added in the other mode and you can not play them.

I was having the same problem when I used Overdrive Media Console to transfer my audiobook files to my Sansa. I updated the license and retransferred and even tried changing the USB settings on the mp2 player. What finally worked? Using Windows Media Player to sync the files instead. When I hooked up my Sansa I chose "use WMP to sync files" and then I dragged/dropped the audiobook files to the mediaplayer window. The audiobook now plays without any problems since WMP made sure the files have the latest subscription update code.

Here's the deal with WMA files - once your subscription expires (or really,  the license on the WMA file expires) - you will have to renew your music service subscription or the song will no longer play on your device. 
Use Mp3 format songs - they'll never give you this problem.

This is what I recieved when I asked a third party for help with this same problem. I worked. Good luck:

The error you are receiving may be
resolved by changing the USB settings within your device. Your device
uses two different transfer modes that are automatically selected by the
device; the primary mode is MTP. MTP mode is what allows the transfer of
the license along with the WMA (Windows Media Audio) title. Can you
please complete the following steps to change the USB setting?

(Please note: Do not connect the device to the computer until step 4.)

1. Power on the device and select 'Settings'.
2. Scroll to and select 'USB Mode' (or 'Mode').
3. Scroll to and select 'MTP' (or 'PlaysForSure Mode').
4. Connect the device to your computer.
5. Open 'My Computer’ > Sansa e280.
6. Delete any WMA (Windows Media Audio) files you see that are of books
you cannot play.
7. Open the OverDrive Media Console and attempt to transfer the audio
book again.