I have a Epson Stylus Photo 1400 that has the capability to print borderless 11 X 14 prints. Lightroom and Photoshop only give me letter, A4, 102 x 152 mm, 89 x 127 mm, Postcard 100 x 148 mm as an option. What do i need to do to add 11 X 14 to the list?
Does this printer have a manual feed system for larger size paper, not an auto feed from a tray? If it does you might have to first start the feeding of that paper so the printer sees you are trying to use that size. It then may then give you that size in its options.
I suggest you Read the Manual.