This can happen when every font used to create a PDF or PostScript document isn't embedded in it, and the necessary fonts aren't installed.
To fix this, install the fonts on your computer that were used to create the original document.
Tip: If you don't know what fonts those are, open the document with
Adobe Reader. You'll see an alert that tell you which fonts were used to create the file and that you don't have installed.
This document will be updated as more information becomes available.
Important: Information about products not manufactured by Apple is provided for information purposes only, and does not constitute Apple's recommendation or endorsement. Please contact the vendor for additional information.