Hi,
I'm developing an upload process from Salesforce to Box to upload files via CORS functionality but I'm failing to make calls to BOX and getting error "XMLHttpRequest cannot load https://upload.box.com/api/2.0/files/content. Origin https://idrdev--c.cs41.visual.force.com is not allowed by Access-Control-Allow-Origin." so could anyone of you please give  me know the solution for this issue?

The Code I'm using to upload files to BOX is..
 

<script type="text/javascript">
    var script= document.createElement('script');
    script.type= 'text/javascript';
    script.src= '//cdnjs.cloudflare.com/ajax/libs/jquery/2.0.0/jquery.min.js';
    document.head.appendChild(script);
    function fileUpload(recId) {
        Visualforce.remoting.Manager.invokeAction(
            '{!$RemoteAction.BoxUploadController.createBoxFolder}',
            recId,
            function(result, event){
                if (event.status) {
                    folderID = result.FolderID;
      		        Bearer = result.Bearer;
                    // Get DOM IDs for HTML and Visualforce elements like this
                    var file =document.getElementById('fileinput').files[0];
                    var form = new FormData();
                    var blob = new Blob([file], { type: file.type});
                    form.append('file',file, file.name);
                    form.append('parent_id', folderID);
                    var uploadUrl = 'https://upload.box.com/api/2.0/files/content';
                    var headers = {
                        Authorization: 'Bearer '+Bearer
                    };
                    $.ajax({
                        url: uploadUrl,
                        crossOrigin: true,
                        headers: headers,
                        type: 'POST',
                        processData: false,
                        contentType: true,
                        data: form
                    }).complete(function ( data ) {
                        console.log(data);
                    });
                } else if (event.type === 'exception') {
                    document.getElementById("responseErrors").innerHTML = 
                        event.message + "<br/>\n<pre>" + event.where + "</pre>";
                } else {
                }
            }, 
            {escape: true}
        );
    }
    </script>

Thanks,
Suman K