The thickness of envelopes and their ability to fold vary widely. If the total thickness of the stack of envelopes exceeds 10 mm, press down on the envelopes to flatten them before loading. If print quality declines when a stack of envelopes is loaded, load one envelope at a time.
You can load up to 10 envelopes at a time in the sheet feeder.
Do not use envelopes that are curled or folded.
Flatten the envelope flaps before loading.
Flatten the leading edge of the envelope before loading.
Avoid using envelopes that are too thin, as they may curl during printing.