First time click on fileupload not working with ajax updatepanel

If we are using fileupload  control inside an AJAX updatepanel, sometimes we face an issue like file upload will not work for first time. In that case add below code in your page_load event.

protected void Page_Load(object sender, EventArgs e)     {         Page.Form.Attributes.Add("enctype", "multipart/form-data");     }