I have tried the solutions listed so far. Neither has worked for me. I use the rear paper tray for card stock and need to find out how to use LibreOffice and card stock. No matter what, I do not find an option for Rear Paper Tray.
Please. Put some effort in your question. Only you can know what solutions you have tried that didn’t work, and you don’t even tell us what printer brand and type you use. How do you expect that we can help you if you keep back essential information?