I have PDF Pro through work. I have used the highlighter in the past but all of a sudden it no longer works on any of my documents, including Word documents converted to PDF. Whenever I go to highlight the word it does nothing except put a blue box around what was highlighted, nothing else. What could I be doing wrong?
It sounds like the file is actually composed of images, not real text. As such, you can't use the Highlighter tool on it, as it's a tool that only works on selectable text. You can use another tool, like the Square tool, with a semi-transparent fill color to get a similar result.
So after messing around with it this morning I have gotten it to work using light red and a different shade of green but the usual highlighter colors still do not work.
And now that I have printed, the yellow highlighted text does show up on the printed paper.