Epson Stylus 1500 Reference Manual page 20

When you load paper in the landscape direction (wider
than it is tall), the rear edge guide may not match the
length of your paper. In this case, remove the rear edge
guide and re-insert it as shown.
8. Lower the output tray to the printing position. Make sure
that the rear edge guide of the paper tray is positioned
under the output tray. The rear edge guide must be under
the output tray to allow room for the paper loaded in the
sheet feeder and to prevent a paper jam.
1-7
Paper Handling