Abstract: A mechanism for sensing the status of a media stack tray which dispenses media to a printing device, the media stack tray being associated with a dispensing device which dispenses media from the media stack tray. The mechanism includes a probe having at least two positions such that the probe is located in a first position when the media stack tray has an empty status and is located in a second position when the media stack tray has a loaded status. The probe is mounted relative to the media stack tray so that when the media stack tray has a loaded status the media is normally located between the probe and the dispensing device. The mechanism also includes a detector for detecting the position of the probe.