Identify cause of No Sensor Defined error message Every active probe looks for a corresponding sensor to process the data that is collected by the probe. The No Sensors Defined message indicates that the corresponding sensor for the probe is missing or inactive. Before you beginRole required: admin About this task To find the cause of this error, identify the Short Message field of the error record. This field shows the name of the probe for which the sensor is missing. Procedure Navigate to Discovery > Discovery Log. Filter on the Level name of Error. You can also view the Error Gauge on the Discovery dashboard. Note the Short Message field of the error record This field shows the name of the sensor. In this example, the sensor error occurred when the Shazzam probe checked for the existence of the Shazzam sensor.