It does it now and again, there is a conflict between the touch screen USB mouse and the GPS. For some reason xport can still pick up its a GPS reciever, but the apps connected to it cant, so I guess its xport screwing something up now and again. Normally it screws the GPS COM port, so have to power it off, remove the USBs, power back up, insert them one by one, GPS will show up on a different COM, then have to change xport to the new COM, and also the 2 that it replicates to, finally change any apps that run off them to point to their new ports. One final reboot releases the original ports and all sorted! Its a right faff, but weirdly only happes maybe twice a year.