I have seen this problem multiple times and can't figure out.  People are opening documents in the viewer and certain text, blocks , features are not showing up on the drawing and when printing.  When you look at the part through the viewer those same features are there.  They are also there when I open them in normal Solidworks.  I have updated their windows fonts and still no luck, why is this happening?  what good is a viewer if it can't show the drawing as it really is?  Is this a computer problem, not enough capacity?