Lexmark X646e User Manual

Load the stack of envelopes flap side down with the stamp area and the flap on the left. The end of the envelopes 
with the stamp area enters the envelope feeder first.

Let the envelopes at the bottom of the stack slide into the envelope feeder slightly more than the ones at the top of 
the stack.

Never use envelopes with stamps, clasps, snaps, windows, coated linings, or self-stick adhesives. 
These envelopes may severely damage the MFP.

When you load envelopes, do not exceed the maximum stack height. Use the stack height label as a 
guide for the correct stack height when loading. Do not try to load more envelopes indicated by the 
stack height label; overloading can cause jams.

Slide the width guide to the left until it lightly touches the stack. Make sure the envelopes do not buckle.

Lower the envelope weight to touch the stack.

Set the Paper Size and Paper Type for the envelope feeder to the correct value for the print media you loaded. 
See 

 for more information.