title: Server side include no longer seems to be working - "[an error occurred while processing this directive]"
body: <p>We have a page that has been using a server side include for many years.  Recently it stopped working.  No changes have been made to the page </p>
  
  <pre><code>&lt;!--#include virtual="..\..\includes\nav.include" --&gt;
  </code></pre>
  
  <p>Near the bottom of a page called contact.html</p>
  
  <p>The 'nav.include' page simply contains html for a navigation bar.  No javascript. No server side scripting. Just html.</p>
  
  <p>Is there some setting somewhere that needs to be set to make SSIs work in the way it is implemented here (including a file with an uncommon extension inside a html file)?</p>