HP Color LaserJet Enterprise M751n Laser Printer - Manual (Page 61)

Use alternative letterhead mode
Use the Alternative Letterhead Mode feature to load letterhead or preprinted paper into the tray the same way
for all jobs, whether printing to one side of the sheet of paper or to both sides. When using this mode, load paper
as for automatic duplex printing.
To use the feature, enable it by using the printer control-panel menus.
Enable Alternative Letterhead Mode by using the printer control-panel menus
1. From the Home screen on the printer control panel, open the Settings menu.
2. Open the following menus:
● Print
● Manage Trays
● Alternative Letterhead Mode
3. Select On , and then press the OK button.
ENWW Load paper to the 2,700-sheet high-capacity input paper trays 51