The software MTP Porting Kit is not needed. If you have firewall software installed on the PC, check it’s setting to ensure it’s not blocking access to USB drives. Check to see if there is some kind of third party USB Manager software installed, if so try disabling it or uninstalling it. My Sansa Clip+ was recognized by my Toshiba laptop with Windows 7 Home Premium right out of the box, no need for extra software or drivers.
Are you guys using the orginal USB cable that came with the Sana Clip or a differnet USB cable? Perhaps its the USB cable that is causing the issue, try the original USB cable that came with the Clip.
