protected void Login1_Authenticate(object sender, AuthenticateEventArgs e)
        {
            bool authenticated = false;
            int doctorId;

                            // return IPAddress
                ClassFunctions newFunc = new ClassFunctions();
                string ipAddress = newFunc.GetUserIP();

            authenticated = this.SiteLevelCustomAuthenticationMethod(this.Login1.UserName, this.Login1.Password, out doctorId);
            e.Authenticated = authenticated;

            if (authenticated == true)
            {
                // capture DoctorId
                this.Session["DoctorId"] = doctorId.ToString();

                // insert into logfile
                this.InsertLogFile(Convert.ToInt32(this.Session["DoctorId"]), ipAddress, "Success", "Login");

                // go
                this.Response.Redirect("DoctorPortal.aspx", true);
            }
            else
            {
                // insert into logfile
                this.InsertLogFile(0, ipAddress, "LoginFailed", "Login");

                this.Login1.FailureText = "Login Username and Password are invalid !";
            }
        }