A family of Microsoft word processing software products for creating web, email, and print documents.
Saving as PDF is essentially a "print" operation, so my guess is that a document sent from one computer to another would display the same problems if printed. This is because cross-references are fields, and fields are updated at print time. This strongly suggests that extraneous content has crept into the bookmark the cross-reference is referencing. For a complete explanation of how this occurs and how to fix it, see http://www.thedoctools.com/demos/demo\_crossref\_3.html.