diff --git a/esp8285/lib/AliyunIoTSDK/src/AliyunIoTSDK.cpp b/esp8285/lib/AliyunIoTSDK/src/AliyunIoTSDK.cpp
index 35e8f0a..2664e82 100644
--- a/esp8285/lib/AliyunIoTSDK/src/AliyunIoTSDK.cpp
+++ b/esp8285/lib/AliyunIoTSDK/src/AliyunIoTSDK.cpp
@@ -118,6 +118,7 @@ static void callback(char *topic, byte *payload, unsigned int length) {
 }
 
 static bool mqttConnecting = false;
+
 int AliyunIoTSDK::mqttCheckConnect() {
     int mqttStatus = 0;
     int connectRetry = 0;
@@ -146,11 +147,11 @@ int AliyunIoTSDK::mqttCheckConnect() {
                     Serial.println(client->state());
                     delay(MQTT_WAIT_GENERIC);
                     connectRetry++;
-                    Serial.print("INFO:\tretry: ");
+                    Serial.print("INFO:\tAliot connection retry: ");
                     Serial.println(connectRetry);
                     mqttStatus = -1;
                     if (connectRetry > MQTT_CONNECT_RETRY_MAX) {
-                        Serial.println("ERROR:\t max connect retry times reached");
+                        Serial.println("ERROR:\tMax connect retry times reached");
                         break;
                     }
                 }
@@ -204,7 +205,7 @@ int AliyunIoTSDK::begin(PubSubClient &mqtt_client,
 #if defined USE_STANDARD_THING_MODEL_TOPIC
     client.setCallback(callback);
 #endif
-    Serial.print("INFO\tconnection check in begin\n");
+    Serial.print("INFO\tConnection check in begin\n");
     return mqttCheckConnect();
 }
 
diff --git a/esp8285/src/aliot_client.cpp b/esp8285/src/aliot_client.cpp
index 821bc7f..19080e9 100644
--- a/esp8285/src/aliot_client.cpp
+++ b/esp8285/src/aliot_client.cpp
@@ -55,13 +55,15 @@ static AliyunIoTSDK iot;
 
 // public function definitions
 int connectToAliot(PubSubClient& mqtt_client) {
-    String aliot_client_id = g_product_key + "." + g_device_name;
-
-    int res = iot.begin(mqtt_client, g_product_key.c_str(), g_device_name.c_str(), g_device_token.c_str(), g_aliot_region.c_str());
+    int res = 0;
+    String aliot_client_id;
+    aliot_client_id = g_product_key + "." + g_device_name;
+    res = iot.begin(mqtt_client, g_product_key.c_str(), g_device_name.c_str(), g_device_token.c_str(), g_aliot_region.c_str());
     if (0 == res && mqtt_client.connected()) {
         INFOF("Aliyun IoT connected\n");
     } else {
         ERRORF("Failed to connect to Aliyun IoT\n");
+        res = -1;
     }
     return res;
 }
diff --git a/esp8285/src/iot_hub.cpp b/esp8285/src/iot_hub.cpp
index f782507..93ed5a8 100644
--- a/esp8285/src/iot_hub.cpp
+++ b/esp8285/src/iot_hub.cpp
@@ -98,7 +98,7 @@ int connectIot() {
     conn_ret = connectToAliot(g_mqtt_client);
 
     if (0 != conn_ret) {
-        INFOF("Try connecting to IoT %s:%d, client_id = %s, user_name = %s, password.size = %d\n",
+        INFOF("Try connecting to EMQX %s:%d, client_id = %s, user_name = %s, password.size = %d\n",
             g_mqtt_server.c_str(), g_mqtt_port,
             g_mqtt_client_id.c_str(), g_mqtt_user_name.c_str(), g_mqtt_password.length());
         conn_ret = connectToEMQXBroker(g_mqtt_client);