title: Internet Explorer Cross Domain: Not sending preflight
body: <p>I've found several similar threads. However, none have yet seemed to work. </p>
  
  <p><strong>Problem</strong></p>
  
  <p>In our current ecosystem we've got three servers for our http-apis. Two for test and one for production. </p>
  
  <p>Recently we've been releasing client-side web applications using AngularJS. Since the client apps is for our customers, the communication to our api is cross domain. The web apps operates properly in Chrome, safari and firefox an all apis. However, for the third api Internet Explorer(11) refuses to send the preflight(options) request, which disables the client to communicate with the api. In the other two apis, the web app works fine in IE.</p>
  
  <p>The apis would be the following: </p>
  
  <pre><code>https://api.doma.in/accesstoken -- Works in IE11
  https://api2.doma.in/accesstoken -- Works in IE11
  https://api3.doma.in/accesstoken -- Does not send preflight in IE11.
  </code></pre>
  
  <p>What is to be noticed is that the three servers are more or less cloned, so the setup won't differ much. </p>
  
  <p>However, the error I'm getting in the error messages I'm getting is the following:</p>
  
  <pre><code>SEC7118: XMLHttpRequest https://api3.doma.in/accesstoken required CORS (Cross Origin Resource Sharing).
  SEC7119: XMLHttpRequest https://api3.doma.in/accesstoken required CORS Preflight.
  SCRIPT7002: XMLHttpRequest Network error 0x80070005, Access Denied.
  </code></pre>
  
  <p>In the network log it only shows that the preflight request got cancelled, hence no request or response headers.</p>