Just a quick note on PDFs.  We had several recent questions about PDFs and what checks we perform and how the results affect the scores.

We perform 2 sets of tests.

Link checks
Accessibility checks

For the links we take a look at and hyperlinks to web pages or mailto: links.  We perform the same level of testing as we do when checking web pages.  So we check a link and make sure the web page is available.  If it works fine, if not it is reported as an error.  We attempt to send an email to all mailto: links we find and if the receiving email server would accept the email that's OK but if the email server rejects our attempt then this is reported as an error.  Usually this is because the email address no longer exists.  We don't actually send an email, as soon as the email server says it will accept the email we cut off.

Accessibility checking is limited to checking that the PDFs have been tagged.  PDF Tags create a text-only representation of the PDF document, which is hidden inside the PDF file and presented to screen readers instead of the original document.  This feature has been available in Adobe Acrobat since version 6.  But I understand that version 7 onwards is a much better implementation of the feature.  We check that the PDF has been tagged.  If it has that's OK if not we flag it as an error.

In terms of how these tests affect the scores:-

The link checks WILL affect the score.
The accessibility tag checks do NOT currently affect the score, but we are reviewing this.

If you'd like more information about how we handle PDFs please look at our Knowledge Base entries at http://www.sitemorse.com/kb.html?query=pdf