I plugged my zune in and the software wouldn't recognize it,

then plugged in my sansa mp3, and the computer didn't recognize it either. However, the computer appears to be charging the devices and my mouse and keyboard are usb and they work. I know they were just working a few days ago, so i tried to roll back my computer a few days with win system restore, that didn't help. I tried starting up my computer with the device plugged in and nothing different. In the device manager, "other devices", "pci modem", "sm bus controller", and if my zune is plugged in "zune" all have a yellow ! by them. I've tried updating the drivers with no luck. I've searched the microsoft site, zune forum, and google and haven't gotten anywhere. Please help.