Can't Download Song and video

hello
i m trying  to download song and video using following code but it only save can't download it
 protected void GridView1_RowCommand(object sender, GridViewCommandEventArgs e)
    {
        if (e.CommandName == "id")
        {
            string url = Convert.ToString(e.CommandArgument);
            //Response.Redirect(url);
            FileInfo fileInfo = new FileInfo(url);
            Response.Clear();
            Response.AddHeader("Content-Disposition", "attachment; filename=" + fileInfo.Name);
        &nbs ...