Hi CLB80
I understand you are getting the message for the media tray to be filled but you can copy.
The media tray is the paper tray. The printer doesn't recognize there is paper in the tray on the computer.
Check the print queue and delete any jobs in the queue.
Go to the Apple, system preferences, click the print and scan icon (on some systems this may be displayed as print & fax) double click the printer on the left side of the window, highlight document in queue and click the delete icon.
Try printing again.
If it still won't print, then the print driver might be corrupted.
I would delete the drivers for the printer and add it back in again.
Click on the Apple.
Click system preferences, click the print and scan icon (on some systems this may be displayed as print & fax) highlight the printer, click on the - sign to delete the printer. Then click the + sign, then select the printer from the list, make sure the printer listed beside use: shows proper printer name and not airprint,(airprint is a preinstalled apple driver with basic funtionality) click on the add button.
I have included a document for a out of paper message to troubleshoot this error. Go up to step three.
If you need more assistance just let me know.