HP 4100TN - Manual (Page 59)

EN Printing special paper 57
Feeding envelopes automatically (optional envelope
feeder)
With the optional envelope feeder, the printer will automatically feed
up to 75 envelopes. To print envelopes without an envelope feeder,
see “Printing envelopes” on page 55.
The envelope feeder supports only standard-size envelopes (see
“Supported sizes and weights of paper - optional envelope feeder” on
page 191).
Note See the documentation included with the envelope feeder for
installation instructions.
You might need to configure the printer driver to recognize the
envelope feeder. See the printer driver online help for details.
Tray
extension
Guides
Envelope
weight
Release lever