I used to ask, what happened in the time between when the printer functioned properly and the time it did not? If we knew what that might help. Off the top of my head it sounds as if the paper tray setting became "manual feed."

You stated that you can print to other printers ok. Can other people print to the problem printer? If others can print without problem to the printer with which you are having problems, then perhaps some configuration setting on your computer was altered. Instead of spending a lot of time, just go to control panel/printers and delete the printer. Then reinstall it (add printer wizard). Does that work?