Every once in a while I get into a situation where Mathematica absolutely insists on tossing in a mysterious double page break and double-printing a cell when I print a notebook. (This is mma 2.2 on a Mac 7100, System 7.)
This usually occurs when I have a notebook with "Show Page Breaks" turned on, and I've selected "Page Break Before Cell" in the Style menu for some cell.
When it happens, as I scroll down through the notebook on screen the page counter in the lower left corner jumps by 2 as I go across a page boundary, and when I print the notebook the first cell just below that boundary prints once at the top of an otherwise blank page, then prints again at the top of the full page it's attached to. (This is printing the entire notebook from the menu command, not executing any Print statements within Mathematica.)
Nothing I can think of seems to get rid of this: If I delete that cell, the problem just moves to a new page break; and messing with the "Page Breaks" options in the Style menu for that cell or any of the adjoining cells above or below it doesn't seem to eliminate the problem.