Printing Problems

I have a score consisting of five saxes, three trumpets, three trombones, piano, bass, and drums. When I print the score, the drumset part is missing. (Also, I tried saving the score as a pdf file and, likewise, the drum part is missing. Additional note: in "Continuous View" and "Single Page" all parts are present, but in "Page View" the drum part is missing.)
What do I need to do?
Thanks.