title: Internet Explorer converting downloaded file.extension to file_extension and other weirdness
body: <p>I'm seeing some weirdness in IE11 that I've never been able to get to the bottom of.  After rebooting, the problem goes away, but I'm trying to isolate what causes it.  The symptoms are:</p>
  
  <ul>
  <li>Certain sans serif fonts in our web application display as Times
  New Roman (even though IE Dev Tools shows that they’re styled
  correctly and downloading) </li>
  <li>When I go to one of our web
  applications,  I get prompted to download the client bits (it doesn’t
  happen automatically like it's supposed to) and when I click the link
  for the downloader, application.exe, it attempts to download it at as
  application_exe.  Some other downloads also get converted to an
  underscore name, but not all.  I just successfully downloaded
  MalwareBytes Anti-Malware tool, so some files get through OK.</li>
  </ul>
  
  <p>Things I’ve tried based on different tips on the web:</p>
  
  <ul>
  <li>IE Safemode (no add-ons running) </li>
  <li>Turning off Enable Protected Mode for all zones </li>
  <li>Unchecked “Do not save encrypted pages to disk” under IE options>Advanced>Security. </li>
  <li>Selected “Enable” on “Enable MIME Sniffing” under IE options> Security
  Settings Internet Zone>Miscellaneous</li>
  <li>Refreshed group policy (gpupdate –force)</li>
  <li>Turned off the Symantec firewall</li>
  </ul>
  
  <p>Any ideas?</p>