You will need to update the firmware in one or two steps depending on how old the firmware version is you are currently running on your unit. Please download and update your unit with either of these older versions of firmware, depending on if you have a sensorProbe2 or sensorProbe8, then update the unit to the latest version that is on our web site. sensorProbe2: https://www.akcp.com/wp-content/uploads/2010/04/SP2_371.zip https://www.akcp.com/wp-content/uploads/2010/04/SP2_398.zip sensorProbe8: https://www.akcp.com/wp-content/uploads/2010/04/SP8_371.zip https://www.akcp.com/wp-content/uploads/2010/04/SP8_398.zip