Our developers created a website that had vCard files for each staff member. The problem was that when people clicked on them, rather than downloading them, some web browsers displayed the content of the file.
Ended up that apache did not know how to handle “.vcf” files. The change below is now part of my standard setup script:
sed -i.ORIG “/text\/xml-external-parsed-entity/a\text\/x-vcard\t\t\tvcf” /etc/mime.types