title: Internet Explorer 9-11 download via iframes started failing
body: <p>I work on an older website that has been functioning for years and after a recent Internet Explorer update we have a iframe based download stop working in IE9-11 most of the time from external networks. It always works fine from our internal network. If we add the site to Trusted Sites it starts working again but that's not going to be a viable solution for our customers.</p>
  
  <p>Would adding a P3P policy to the site correct this issue or is there something else we need to do?</p>