If you have checked to make sure the sensors are connected to the computer, most likely you either have the finger sensors on upside down (make sure the double latches are over your fingernails) or your hands are too dry (try applying moisturizer on your fingers before using the finger sensors).

If you have both emWave and IOM sensors, make sure only one is plugged in (the one you want to use with Alive). Occasionally restarting the computer may be required.

If your finger sensors used to work on your IOM, but now have stopped working, you will need to purchase a replacement IOM or Lightstone sensor, these are no longer manufactured but open box models can be purchased from www.somaticvision.com/Lightstone.