The document doesn't print at all, or do you mean that the watermark doesn't print?
Also, what does "doesn't print" mean, exactly?
And what application (including exact version number) are you using?
I have adobe professional XI. The document will stall in printing, and then give an error message and need to be cancelled in the print cue. It only happens with documents that have a watermark and that are also long. There is a work around I found. It is in the Adobe help, but buried under print problems. File, print, advanced. Then print as image. Then ok. Then print, then ok. It works!