CORS using ExtJS returns error 405 (Method not Allowed)

Question

I'm trying to use CORS to get data from another WS using ExtJS. The page that is calling this request is loaded over HTTPS and the requested page is HTTP.

Ext.Ajax.request({
  url: 'http://MYDESTINATIONURL',
  method: 'GET',
  disableCaching: false ,
  useDefaultXhrHeader: false,
  cors: true,
  success: function(response) {
    console.log('SUCCESS!');
  },
  failure: function(response) {
    console.log('FAILURE!: '+response.getAllResponseHeaders());
  }
});

This request generates an OPTIONS method with a 405 (Method not Allowed) status. More details on the request: Request Method:OPTIONS Status Code:405 Method Not Allowed

Request Headers
Accept:*/*
Accept-Encoding:gzip,deflate,sdch
Accept-Language:pt-PT,pt;q=0.8,en-US;q=0.6,en;q=0.4
Access-Control-Request-Headers:x-requested-with
Access-Control-Request-Method:GET
Cache-Control:max-age=0
Connection:keep-alive
Host:MYDESTINATIONURL
Origin:https://localhost
User-Agent:Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko)         Chrome/35.0.1916.153 Safari/537.36

Response Headers
Access-Control-Allow-Headers:X-Requested-With,Content-Type
Access-Control-Allow-Origin:*
Access-Control-Request-Method:POST,GET,PUT,DELETE,OPTIONS
Allow:GET
Content-Length:1565
Content-Type:text/html; charset=UTF-8
Date:Tue, 22 Jul 2014 12:06:02 GMT
Server:Microsoft-HTTPAPI/2.0

The headers are according to CORS, I think. The request contains the Origin header and the response contains the -Allow-Origin header. The server supports CORS. What is causing the error though?

The error: OPTIONS http:// MYDESTINATIONURL 405 (Method Not Allowed) XMLHttpRequest cannot load http:// MYDESTINATIONURL. Invalid HTTP status code 405

Answer 1

I had the same problem as mentioned above, but resolved it by adding the following two lines during my application initialisation:

Ext.Ajax.useDefaultXhrHeader = false;
Ext.Ajax.cors = true;

Prior to this I had attempted to set the useDefaultXhrHeader and cors parameters on my store's AjaxProxy without any success.