Epson AcuLaser C8600 Reference Manual page 112

If the USB device driver is not installed correctly, EPSON USB
Printer Devices may not appear. Follow these steps to run the
"Epusbun.exe" file in the CD-ROM that comes with your
printer.
1.
2.
3.
4.
3. Follow the on-screen instructions.
110 Using the Printer Software with Windows
Insert the CD-ROM in your computer's CD-ROM
drive.
Access the CD-ROM drive.
Double-click the Win9x folder.
Double-click the Epusbun.exe icon.