It means AHP thinks the switch is open. Try opening/closing the door/window/switch and checking Tools > Activity Monitor... in AHP to see if you are getting reliable RF signals from the DS10A. If your experience is anything like mine, you're not getting reliable open/close signals from the DS10A to the CM15A.
If you are using a stock CM15A and the sensor is more than a few feet away, odds are you're missing signals. There are a number of posts discussing how to increase the RF range of the CM15A. Try a search for "CM15A range" -- the sheer number of topics and postings should be an indication that this is a common problem!