My mp3 player (sansa m200 512 MB) will not show up as a drive on one of my computers (both running XP Pro). When I first plugged it in, I got the "found new hardware, MTP Media player" balloons. It shows up in device manager under "windows portable device". There are no USB conflicts in device manager. Whenever I now plug it in, I get the MTP media player window, but if I try to synch using WMP10, it says that WMP does not detect a portable device, nor will it show up as a device in windows explorer or my computer. My older iriver jukebox (iHP 120) shows up on as expected, but both newer players I've tried (this sansa m200 and an iRiver T10)won't. Both showed up as expected on my other computer. Any suggestions?

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