I've searched high on low on this forum (and Google/Apple Support) for a fix for this. Certain PDfs won't open in Preview. Instead this message appears: To view the full contents of this document, you need a later version of the PDF viewer. You can upgrade to the latest version of Adobe Reader from etc etc." Which is nonsense since I have the latest version. It usually happens on PDFs mailed to me from official government bodies. Get Info on the file indicats that the Encoding software is Adobe LiveCycle Designer ES 8.1 Any advice would be most appreciated.