It’s a Microsoft thing, actually. Files transferred in MTP Mode will not be visible while in MSC Mode , making for “invisible” files when using Windows Explorer.
The culprit is the system registry of your PC. When it enumerates, or queries the device upon finding it on the USB port, the Sansa is ignored. Why would your PC do such a thing? Simply, the registry is the computer’s “cheat sheet”, telling it what to do with the device.
When you installed that webcam , the registry entry was lost in translation, so to speak. Most often, uninstalling the connected sansa, then reinstalling automatically upon reconnect, will fix the problem. Windows is seeing the device, and then runs to the cheat sheet next, rather than performing a reinstallation. It looks like the device is “broken”, since it suddenly isn’t recognized.
Here’s the most important point: the Sansa will happily communicate in either mode, and will display all music files regardless of mode. From the computer, you can’t see both modes at the same time.
Where does Windows Media Player fall into this equation? Simply, MTP Mode , where the Sansa is recognized as a media player or portable device rather than a flash drive, is part of WiMP10 and later. Please note that you don’t have to use WiMP directly in MTP mode, since MTP is possible through Windows Explorer too. In MTP, you’ll see the Sansa lister under “other” as a media device; a double click opens the device into Internal Memory and External.
MTP is a virtual mode supported by Windows Media Player, allowing the transfer of protected content to your device. Since it’s seen as a media player in this mode, you can also do some cool things like generate playlists via a right click, and album art transfer is automated too.
To reestablish MTP “connectivity” or communication (would we say “communicationivity”- some computer terms are simply crazy), manually select MTP on the Sansa via Settings > USB Mode > MTP, and plug in. Open the Device Manager via a right click on My Computer, then select manage , then open the device manager. In the listing, the Sansa should be listed under “portable device”. Double click, or right click on it, and select uninstall.
How simple was that! Unplug the cable, and try plugging in again after at least 30 seconds, allowing the PC to make changes. The device should now show up in Windows Explorer like it used to.
Many users opt to simply use MSC Mode exclusively, since it is what I’d call a manual, or direct mode. This mode works great for drag and drop of unprotected mp3 or wma files. If you have DRM protected media, MTP is needed.