HP Color LaserJet 3800 Printer series - Manual (Page 71)

Loading paper into tray 1
CAUTION Avoid adding print media to tray 1 while the printer is printing, or jams can occur.
1. Open tray 1.
NOTE If printing on special media, such as envelopes, use tray 1. See Printing envelopes
from tray 1 for more information.
2. Slide the output bin extension out from the bin.
3. Slide out the tray extender and, if necessary, open the additional tray extender.
ENWW Configuring trays 57