Epson EPL-6100 Reference Manual page 106

Note:
If your computer is running Windows 98, 95, XP, 2000, or NT 4.0, you
can also confirm that the 500-Sheet Lower Paper Cassette Unit A4 is
correctly installed by checking the information displayed in the printer
driver's Optional Settings menu.
Loading Paper
Follow the steps below to load paper into the 500-Sheet Lower
Paper Cassette Unit A4:
1. Pull the paper-tray out from the cassette unit.
4 Installing and Removing Options