Is this a scanned document? The highlighter gets it's information from the geometry of the text that you are trying to highlight. If you don't have "real" text in your document (e.g. a scanned document that was OCR'ed), then this information is coming from text that is hidden behind the scanned image. If it's not a scanned document, then there is something else wrong with that text. What is the PDF Producer and Application information in the Document Information dialog (Ctrl-D or Cmd-D)?
Karl Heinz Kremer
PDF Acrobatics Without a Net
PDF Software Development, Training and More...
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