OPTIONS 405 (Method Not Allowed)

Question

So I'm attempting to get a progress bar on file uploads on my site. If I simply upload the resource

$.ajax({
    url: $rootScope.URL,  //Server script to process data
    type: 'POST',
    beforeSend: beforeSendHandler,
    success: completeHandler,
    error: errorHandler,
    data: formData,
    cache: false,
    contentType: false,
    processData: false
});

It works perfectly, however if I add the event to listen to progress:

$.ajax({
    url: $rootScope.URL,  //Server script to process data
    type: 'POST',
    xhr: function() {  // Custom XMLHttpRequest
        var myXhr = $.ajaxSettings.xhr();
        if(myXhr.upload){ // Check if upload property exists
            myXhr.upload.addEventListener('progress',progressHandlingFunction, false); // For handling the progress of the upload
        }
        return myXhr;
    },
    beforeSend: beforeSendHandler,
    success: completeHandler,
    error: errorHandler,
    data: formData,
    cache: false,
    contentType: false,
    processData: false
});

I get:

OPTIONS myserver.com/controller/filtercontroller.php? 405 (Method Not Allowed)
  jQuery.ajaxTransport.send 
  jQuery.extend.ajax    
  (anonymous function)  
  jQuery.event.dispatch 
  jQuery.event.add.elemData.handle  
XMLHttpRequest cannot load myserver.com/controller/filtercontroller.php?. No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://localhost:63342' is therefore not allowed access. The response had HTTP status code 405.

So obviously my server doesn't have Access-Control-Allow-Origin and OPTIONS right? But the top 2 lines of filtercontroller.php are:

header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: GET, POST, OPTIONS');

I've tried several different solutions and none have worked for me.

Answer 1

So, first of all I do not think it has anything to do with your CORS configuration, as it would output different errors. Looking into what can cause the error you are receiving in the context of Azure/IIS I found the following possibilities:

• You might have an explicit <remove name="OPTIONSVerbHandler" /> in your web.config file. (This is the default in certain cases).
• The WebDAV module is interfering and you should add <remove name="WebDAVModule"/>

Lastly I just found this answer which might offer some different solutions where you do not set the CORS headers in your PHP file, but instead set them in the server configuration.