"I have assumed that you mean "Sensor Settings", "Temperature 1", "Calibration" and that you have skipped the "Sensor Settings" menu. (or I guess you mean press the button on the front of the controller with C on it)?

Either way my next post states that I did this "From the main menu, I selected sensors, temp 1, calibration. (I think this was the path, as I am typing this at work)"

this is the right way to restore the calibration. If you had answered my question about the currently displayed ADC-values (in ProfiLuxControl) I could say you for sure if the calibration is the problem or not.
Please tell me ADC1 and ADC2.