I have a HP Photosmart B8550 printer for printing up to 13 x 19. Usually I use it just for 11 x 17. Lately if I try to print an autocad dwg at 11 x 17 it prints in portrait mode. If I change the print setup to Landscape mode - it prints in portrait mode. I printed the files to pdf files and used preview to print : portrait = portrait, landscape = portrait. I'm about ready to scream. Sometimes it works - I just wasted about 1 hr and have a whole bunch of drawings printed across the middle of the page. Printer is hooked up on USB port and I'm running Yosemite (mid 2010 macbook pro) aaargh!