diff --git a/WifiControlSensor/MQTT.ino b/WifiControlSensor/MQTT.ino
index 61df5c0..2165d7f 100644
--- a/WifiControlSensor/MQTT.ino
+++ b/WifiControlSensor/MQTT.ino
@@ -76,8 +76,9 @@ Adafruit_MQTT_Publish *MqttCreatePublisher(const char *fmt, ...){
 bool MqttIsConfigured() {
   return isMqttConfigured;
 }
+
 int MqttIsConnected() {
-  return mqtt->connected();
+  return (mqtt != NULL) ? mqtt->connected() : 0;
 }
 
 // Function to connect and reconnect as necessary to the MQTT server.
@@ -85,6 +86,9 @@ int MqttIsConnected() {
 int MqttConnect() {
   int8_t ret;
 
+  if(!isMqttConfigured)
+    return -1;
+
   // Stop if already connected.
   if (mqtt->connected()) {
     return 0;