title: HTTP Cache - check with the server, always sending If-Modified-Since
body: <p>I have a resource which is user generated and therefore changes at an unpredictable time (example, a user uploads a new version of a word document).  I would like browsers to cache this resource and validate its cache with the server on each request (i.e. always send the If-Modified-Since header).</p>
  
  <p>From testing, I've found that Firefox handles this appropriately when I use "Cache-Control: no-cache" in the response header.  However, Internet Explorer 7 is not sending "If-Modified-Since" in its request header.</p>
  
  <p>Does "Cache-Control: no-cache" achieve what I described at the beginning?  If not, is there anything I can do differently to achieve what I've described across browsers?</p>
  
  <p>Thanks.</p>