After 2 weeks of installing, uninstalling, updating software, buying a new data cable, rebooting, etc...ect.... I finally got MPT to work with my Motorola V551 phone. You'll never belive what worked. Are you ready for this? Are you sure? I TURNED THE PHONE OFF AND BACK ON AGAIN! Now everything works as it should. I'd kick myself if I could. Try it! It may work for you too!