OK. I should have asked what type printer you are using: laser, ink jet, &c.
If it is a laser (either PostScript or HPGL) you will probably have to go
through your documents and change the character you use for a check box to
an actual box glyph from a symbol font. Those that look like boxes in other
fonts are probably not actual boxes but "no data present for this glyph" or
"glyph not defined for this code point" default markers and XP will print
nothing for such markers on printer types that use their in-built
rasterisers for rendering. Printer types that use the Windows rasteriser,
the one Windows uses to draw or render the screen, (ink jets, for example)
will print the same as the screen.
The task is eased by using Find/Replace or writing a macro.
Let us know.
Tom
MSMVP-DTS