HP LaserJet 9050 Printer series - Manual (Page 106)

104 Chapter 6 Problem solving ENWW
5 Open the front door.
6 Check for paper in the duplex printing accessory area, and remove any paper by pulling it out
of the printer. Be careful not to tear the paper.
7 Reinstall the duplex printing accessory by sliding it back into the slot until it locks into place.
8 Close all open doors. If an optional output device is installed, push it back into place.