$.ajax async:false doesn't work in IE and Firefox, works in Chrome/Safari
ajax, asynchronous, javascript, jquery
Solution
IE 8/9 cross domain requests require jQuery to use a different transport method which uses a XDomainRequest instead of the default XmlHttpRequest.
I believe the question has been answered already here: [question]: CORS with jQuery and XDomainRequest in IE8/9
For FireFox try setting the "dataType" of the content returned by the $.ajax request.
Problem
I am trying to measure download speed with ajax call. Here is the my code ``` var start = new Date(); $.ajax ({ url: 'https://www.example.com/perftest/dummyFile1024', cache: false, success : function() { var total = (new Date() - start) alert(total) }, error : function(jqxhr, status, ex) {} }) ``` It doesn't wait until whole file loaded. When I add `async: false,` it waits for loading whole file and I am able to measure bandwidth at chrome and safari however internet explorer and firefox still works the same as `async: true,` they don't wait until whole file loaded. Do you have any idea how I can manage it works for I.E. and firefox as well? Thanks.