The Multipurpose Feeder, or Multipurpose Tray (MPT), is a paper source that comes as standard on most printers. (Note: Only certain Optra S24xx series and Optra Se3455 will have an MPT.) The MPT supports the printing of envelopes as well as paper, cardstock, labels, and transparencies. The paper size for the MPT must be selected on the front panel of the printer. For any Optra S/Se printer with the Multipurpose Feeder installed, you will find three choices for the feed function of the MPT under the Paper Menu: Cassette, Manual, First. Cassette: This is the factory default setting. If this is selected, the MPT will act like one of the paper trays - that is, it will continually pull paper until it is empty. In addition, if the paper size requested by the software does not match the size selected on the front panel of the printer, the printer will post a change paper message or find another tray that has that paper size and type loaded. Manual: This setting allows you to feed a single sheet at a time. The printer will prompt you to load the sheet of paper or envelope in the MPT. Once you have loaded the media, the printer will pull the paper in. First: This setting will allow you to bypass any tray selections in the software. If the software asks for any other trays, the printer will first check to see if any paper is loaded in the MPT. If it is empty, the printer will then print from the requested tray. However, if there is any paper loaded in the MPT, the printer will go ahead and pull from the feeder until it is empty. Once the feeder is empty, it will proceed to pull from the chosen paper tray. Note: If Configure MP is set to First, the printer will assume the paper type of the tray that was requested. For example, if tray 1 is set to Cardstock and Configure MP is set to First, a print job requesting tray 1 will use cardstock as the paper type if paper is pulled from the MPT.