Solution folder content invisible in visual studio

Asynchronous file upload :

<asp:asyncfileupload id="btnUpload" runat="server" xmlns:asp="#unknown">
                        onuploadedcomplete="btnUpload_UploadedComplete" UploaderStyle="Modern" 
                        CompleteBackColor="White" UploadingBackColor="#CCFFFF"
                            ThrobberID="imgLoader" OnClientUploadComplete="uploadComplete" 
                        OnClientUploadStarted = "uploadStarted"  Width="120px" 
                        ClientIDMode="Static" CssClass="FileUploadWidth" FailedValidation="False"
                         />

 protected void btnUpload_UploadedComplete(object sender, AjaxControlToolkit.AsyncFileUploadEventArgs e)
        {
            try
            {
                File.Delete(string.Format(@"{0}\{1}", Server.MapPath(this.UploadFolderPath), "Test.jpg"));
                filename = System.IO.Path.GetExtension(btnUpload.PostedFile.FileName).ToString();
                btnUpload.SaveAs(Server.MapPath(this.UploadFolderPath) + "Test" + filename);
                imgDisplay.Src = this.UploadFolderPath + "Test" + filename;
            }


            catch (Exception ex)
            {

            }

        }


javascript 

<script type = "text/javascript">
     function uploadStarted() {
         $get("imgDisplay").style.display = "none";
     }
     function uploadComplete(sender, args) {
         var imgDisplay = $get("imgDisplay");
         imgDisplay.src = "images/loader.gif";
         imgDisplay.style.cssText = "";
         var img = new Image();
         img.onload = function () {
             imgLoader.style.cssText = "height:171px;width:150px";
             imgLoader.src = img.src;


         };
         var fileName = "";
         fileName = args.get_fileName();
         var fileExtension = fileName.substring(fileName.lastIndexOf('.') + 1);

         img.src = "<%=ResolveUrl(filename) %>" + "Test." + fileExtension;
     }

    </script>
</asp:asyncfileupload>