title: Not allowed page to open in other tab
body: <p>We have 1 page and we are doing some calculation of data which takes about 20 min. If I open a new tab and try to explore the site whilst the calculation is running, I am unable to access the application and the new tab is stuck loading the page till the first tab process gets completed.</p>
  
  <p>We are using MVC4 and it is an ajax call, the code of which is below.</p>
  
  <p><strong>Why it is preventing me from accessing the application in another tab when the calculation is running?</strong></p>
  
  <pre><code>$.ajax({
      url: '/Administration/Recalculate',
      type: 'POST',
      data: postData,
      cache: false,
      traditional: true,
      success: function (entityObj) {
          HideProgress("spinnerForInflationIndex");
          $("#spinnerForInflationIndex").hide();
          alert("Recalculation of Inflation Index has been done successfully, please check the log file. You may be redirected to the Login page due to session time out.");
      },
      error: function (response, status, error) {
          HideProgress("spinnerForInflationIndex");
          $("#spinnerForInflationIndex").hide();
          //Display error message
          DisplayErrorMessage(response, true);
      }
  });
  </code></pre>