Epson AcuLaser C3900N User Manual page 153

AcuLaser C3900 Series User's Guide
5. Close the right side cover of the 500-sheet paper cassette unit.
6. Reconnect all interface cables.
7. Reconnect the power cord, and turn on the printer.
8. Declare Paper Source Unit 3 in the Windows printer driver (Properties/Configure tab).
Installing Accessories 153