Una forma de administrar Error en Global.asax

void Application_Error(object sender, EventArgs e)

        {

            Exception err = Server.GetLastError();

            if (err != null)

            {

                if (HttpContext.Current.Server != null)

                {

                    Response.Clear();

                    string data = @"

                    <div style='text-align:center; font-size:15px;'>

                        <img src='url.png' style='margin: 0 auto;' alt='' />                 

                    <hr>

                    <a href='/Home/Index'>Volver a pantalla de búsqueda</a>

                    </div>

                    ";

                    Response.Write(data);

                    Server.ClearError();

                }

            }

        }