Load Envelopes You can print on envelopes in 4 1/8 × 9 1/2 inch (#10) size. 1. Open the paper support and flip up the extension. 2. Extend the output tray. 3. Flip the feeder guard forward. Squeeze the edge guide and slide it left. 4. Load up to 10 envelopes against the right side and beneath the tab. Load them printable side up and flap edge left. Tip:Press each envelope flat before loading it or load one envelope at a time. 5. Slide the edge guide to the edge of the envelopes, but not too tightly. See also: Load Paper for Photos Load Paper for Documents