HP Deskjet 3050A - Manual (Page 23)

b. Lower the output tray
Lower the output tray and pull out the tray extender.
c. Slide paper-width guide to the left.
Slide paper-width guide to the left.
Remove all paper from the main input tray.
d. Load envelopes.
Insert one or more envelopes into far-right side of the input tray. The side to be printed on should face up. The flap
should be on the left side and facing down.
Slide stack of envelopes down until it stops.
Slide paper-width guide to the right against stack of envelopes until it stops.
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