Hi, Finally I have returned... Sorry for delayed response. I know if I use AddFilter to add to the capture graph, I can tell whether the device is there. However, I think that means I have to disrupt it, i.e., eliminate it from the capture graph and then reconnect it. That would interrupt the video. I tried your suggestion but it answers S_OK even when the camera is not attached! Like I said, this is a pathological case caused by the method used by this older QuickCam. It is set up so that you have to use "Unplug or Eject Hardware" to make the driver go away. Newer systems handle this automatically. Wonder if I can figure out what the "Unplug or Eject Hardware" function is doing? If I could, then maybe I could use that to determine the status. I will continue looking at functions that might be used to determine status. Your idea gave me some other ideas to try... Thanks, Howard Howard C. Anderson HTTP://www.astroshow.com