There is no option in the Page Setup menu to select the envelope cassette. If Universal Cassette is selected you get the paper out indication. You must select Auto Select in the Page Setup menu. You must do this because the software looks at what type of paper is being selected in the Page Setup and checks each cassette until it finds that size paper.
In order to print an envelope with the optional envelope tray on the LaserWriter Select 360, follow these steps:
1) Open the application program
2) Choose Page Setup from the File menu
3) Select envelope size (Comm 10 for business envelopes)
4) Select Landscape
5) Select OK
6) Choose Print from the File menu
7) Select Auto Select
8) Select Print
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