I called Hamilton support today (1-800-837-5561) and they dialed into my modem and checked out my credit card computer. They said that the unit was turned off for a very long time and it was reset a lot of times. So apparently they can not really check anything by dialing into the system. (I knew that much!) They did say to send the unit in to them and they think it will cost anywhere between $200 and $500 to fix.