Published file with link to pdf problems

Hi

I have published a course with 2 links to pdf documents.  The pdfs look at they should when I view the published file locally.  However, when I look at the published content on the clients Sharepoint site, the pdfs show up as just one page (almost like an image).  What's strange is that other pdfs work as they should in the content.  I'm stumped. .  .