An addendum to my last post. (If it is a font problem.) Fonts that are .SHX files just have to be in one of the file search paths in your preferences, eg. in the same directory as the drawing. The fonts that have to be installed on every computer are the .ttf font files.
Be sure you have the font installed. Sometimes if you don't have the font installed, ACAD will substitute another font for it, and the text will show up on the screen but won't print. >You have to have the font installed on the computer you are printing from.< We run into this sometimes with...