USB:
Mac - Unplug the USB and plug into a different port or same port (Try Both). If this does not trigger the print go into the printer queue and delete all jobs, REBOOT. If that does not resolve the issue check the usb cable by swapping it out with another.
PC - Reboot Computer, go into Control Panel - Devices and Printers, Right Click on the printer and click on "See Whats Printing". Highlight the document and click the document drop down menu and click restart. If there are no jobs in the queue resend the job from your printing software after following the first set of instructions on reboot. IF this does not resolve the issue, check the USB cable by swapping it out with another.
ETHERNET:
Check that the IP address assigned to the printer matches the IP address assigned on the computer.
MAC & PC: Use Epson Net Config program to search the network for printers (found on Epsons web site under the support page for the printer you have).
Updating your IP Address:
MAC - Subtract the printer from the printer list and ADD printer. After you click the + button to add the printer, choose the IP Icon at the top of the add window. Type in the IP address of the machine (found either on the panel of the printer or through the Epson Net Config software. Name the printer and choose the driver software (computer should do this automatically). click ADD at the bottom right of the window. Restart any open programs and resend the print.
PC - Go to "Devices and Printers" on your computer. right click on the printer, choose "Printer Properties", then choose "Ports", Then look for the port address that was given from Epson Net Config and check and apply the selection that matches the IP. If there is no setting that matches the IP address, click "Add Port", Then choose Standard TCP/IP Port, Click New Port..., Go through the wizard software to add the port. After Adding the port make sure to select it on the Ports page and hit "Apply" to activate the port. You should see the printer name populate after you hit apply.