I have been setting up some course prototypes using pdf files converted from Word docs as resources (link to uploaded file). For awhile I tried various third-party doc-to-pdf downloads and settled on an evaluation copy of Blue Point Light. Later I got a copy of Acrobat from my school. All the pdf files display correctly in windows outside a browser. They also display correctly as resources in Moodle using IE. But when I try to display the non-Acrobat pdfs through Firefox, I get an error: "file does not start with %pdf-". I believe these pdfs were made using Blue Point. I don't understand why the browser would make a difference.
It isn't a pressing problem because the files I convert with Acrobat work fine so I just reconvert the old ones, but I wonder if anyone else has run across this or if anyone understands it. It makes me a little uneasy about using pdf format since many of our students use Firefox, but pdf also has many advantages, so if the problem is predictable and preventable I would like to use pdf.