Oki C9300dn User Manual page 196

Removal
The duplex unit may be removed from the printer as follows.
Switch off the printer and disconnect the power cable.
1.
Open the small front cover and pull the coloured handle (1) to
2.
slide the duplex unit/paper tray out of the printer as a
complete unit.
Slightly lift up the duplex unit/paper tray together and remove
3.
completely from the printer.
Pull the post (2) forward and pull the two stoppers (3) forward
4.
to release the duplex unit from the paper tray, then remove the
duplex unit from the paper tray.
Refit the front cover to the printer, then reinstall the paper tray.
5.
Connect the power cable and switch the printer on.
6.
Press the Menu button until PRINT MENU is displayed, then
7.
press the Select button.
Press the Item (+) or (–) button until DUPLEX is displayed.
8.
Press the Value (+) or (–) button until OFF is displayed and
9.
press the Select button. An asterisk (*) appears to show that
duplex has been set to OFF.
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