MQTT Error with ESP8266

I always get this Error Message when I try to connect to my CloudMQTT Server.

Attempting MQTT connection...failed, rc=5 try again in 5 seconds.

This is my Code:

#include <ESP8266WiFi.h>
#include <PubSubClient.h>

const char* ssid = "3Tube_2.4Ghz_B8F6";
const char* password = "4747740628";
const char* mqttServer = "m24.cloudmqtt.com";
const int mqttPort = 18730;
const char* mqttUser = "wcbrsghi";
const char* mqttPassword = "D2-02MINipLd ";

WiFiClient espClient;
PubSubClient client(espClient);

const int lamp = 4;

long now = millis();
long lastMeasure = 0;

void setup_wifi() {
delay(10);

Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.print("WiFi connected - ESP IP address: ");
Serial.println(WiFi.localIP());
}

void callback(String topic, byte* message, unsigned int length) {
Serial.print("Message arrived on topic: ");
Serial.print(topic);
Serial.print(". Message: ");
String messageTemp;

for (int i = 0; i < length; i++) {
Serial.print((char)message*);*
_ messageTemp += (char)message*;_
_
}_
_
Serial.println();*_

* if(topic=="room/lamp"){*
* Serial.print("Changing Room lamp to ");*
* if(messageTemp == "on"){*
* digitalWrite(lamp, HIGH);*
* Serial.print("On");*
* }*
* else if(messageTemp == "off"){*
* digitalWrite(lamp, LOW);*
* Serial.print("Off");*
* }*
* }*
* Serial.println();*
}
void reconnect() {

* while (!client.connected()) {*
* Serial.print("Attempting MQTT connection...");*
* if (client.connect("ESP8266TestClient")) {*
* Serial.println("connected"); *
* client.subscribe("room/lamp");*
* } else {*
* Serial.print("failed, rc=");*
* Serial.print(client.state());*
* Serial.println(" try again in 5 seconds");*

* delay(5000);*
* }*
* }*
}
void setup() {
* pinMode(lamp, OUTPUT);*
* Serial.begin(115200);*
* setup_wifi();
_
client.setServer(mqttServer, mqttPort);_
_
client.setCallback(callback);_
_
}_
void loop() {
_
if (!client.connected()) {_
_
reconnect();_
_
}_
_
if(!client.loop())_
_
client.connect("ESP8266TestClient" , mqttUser, mqttPassword);_
_
now = millis();*_

* if (now - lastMeasure > 30000) {*

_ char* t = "26.7";_

* client.publish("room/temperature", t);*
* Serial.print("Temperature: ");*
* Serial.print(t);*

* }*
}

First use a test program on your PC such as MQTT Explorer, MQTTLens or MQTT.fx to check to see if a connection can be made to the server.