Problems compiling Firebase, FirebaseEsp32,WiFi and IOXhop_FirebaseESP32.h Libraries

Dear friends,

When I'm compiling the program, this message appears below:

In file included from C:\Users\VNH\Documents\Arduino\libraries\Firebase_ESP32_Client\src/Firebase.h:45:0,
                 from C:\Users\VNH\Documents\Arduino\libraries\Firebase_ESP32_Client\src/FirebaseESP32.h:49,
                 from L:\Engenharia-Eletronica\Projetos\Esp32\LedOn-Firebase\LedOn-Firebase\LedOn-Firebase.ino:7:
C:\Users\VNH\Documents\Arduino\libraries\Firebase_ESP32_Client\src/signer/Signer.h:56:24: error: redefinition of 'class FirebaseESP32'
 #define FIREBASE_CLASS FirebaseESP32
C:\Users\VNH\Documents\Arduino\libraries\Firebase_ESP32_Client\src/Firebase.h:289:7: note: in expansion of macro 'FIREBASE_CLASS'
In file included from L:\Engenharia-Eletronica\Projetos\Esp32\LedOn-Firebase\LedOn-Firebase\LedOn-Firebase.ino:5:0:
C:\Users\VNH\Documents\Arduino\libraries\IOXhop_FirebaseESP32-master/IOXhop_FirebaseESP32.h:23:7: error: previous definition of 'class FirebaseESP32'
 class FirebaseESP32 {
Foram encontradas múltiplas bibliotecas para "WiFi.h"
Usado: C:\Users\VNH\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\WiFi
Não usado: C:\Program Files (x86)\Arduino\libraries\WiFi
Não usado: C:\Users\VNH\Documents\Arduino\libraries\WiFi
Foram encontradas múltiplas bibliotecas para "SD.h"
Usado: C:\Users\VNH\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\SD
Não usado: C:\Program Files (x86)\Arduino\libraries\SD
Usando a biblioteca WiFi na versão 1.0 na pasta: C:\Users\VNH\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\WiFi 
Usando biblioteca IOXhop_FirebaseESP32-master na pasta: C:\Users\VNH\Documents\Arduino\libraries\IOXhop_FirebaseESP32-master (legacy)
Usando a biblioteca HTTPClient na versão 1.2 na pasta: C:\Users\VNH\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\HTTPClient 
Usando a biblioteca WiFiClientSecure na versão 1.0 na pasta: C:\Users\VNH\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\WiFiClientSecure 
Usando a biblioteca ArduinoJson na versão 5.0.0 na pasta: C:\Users\VNH\Documents\Arduino\libraries\ArduinoJson 
Usando a biblioteca Firebase_ESP32_Client na versão 3.11.4 na pasta: C:\Users\VNH\Documents\Arduino\libraries\Firebase_ESP32_Client 
Usando a biblioteca SPI na versão 1.0 na pasta: C:\Users\VNH\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\SPI 
Usando a biblioteca FS na versão 1.0 na pasta: C:\Users\VNH\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\FS 
Usando a biblioteca SPIFFS na versão 1.0 na pasta: C:\Users\VNH\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\SPIFFS 
Usando a biblioteca SD na versão 1.0.5 na pasta: C:\Users\VNH\AppData\Local\Arduino15\packages\esp32\hardware\esp32\1.0.6\libraries\SD 
exit status 1
Erro compilando para a placa ESP32 Wrover Module

Bellow is the source code of the program:

#include <WiFi.h>       // esp32 library

#include <IOXhop_FirebaseESP32.h>   // firebase library

#include <FirebaseESP32.h>

#define FIREBASE_HOST ""     // the project name address from firebase id

#define FIREBASE_AUTH "Key XXXXXX"   // the secret key generated from firebase

#define WIFI_SSID "VNH 2.4GHZ"      // input your home or public wifi name

#define WIFI_PASSWORD "13092015"      //password of wifi ssid

String fireStatus = "";                                                     // led status received from firebase

int led = 2;                                                               

void setup() {



  pinMode(2, OUTPUT);                

  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);                                      //try to connect with wifi

  Serial.print("Connecting to ");


  while (WiFi.status() != WL_CONNECTED) {





  Serial.print("Connected to ");


  Serial.print("IP Address is : ");

  Serial.println(WiFi.localIP());                                                      //print local IP address

  Firebase.begin(FIREBASE_HOST, FIREBASE_AUTH);                                       // connect to firebase

  Firebase.setString("ligar-led-esp32", "OFF");                                          //send initial string of led status


void loop() {

  fireStatus = Firebase.getString("ligar-led-esp32");                     // get led status input from firebase

  if (fireStatus == "ON") {                         // compare the input of led status received from firebase

    Serial.println("Led Turned ON");                 

    digitalWrite(2, HIGH);                                                         // make output led ON


  else if (fireStatus == "OFF") {              // compare the input of led status received from firebase

    Serial.println("Led Turned OFF");

    digitalWrite(2, LOW);                                                         // make output led OFF


  else {

    Serial.println("Wrong Credential! Please send ON/OFF");



What could be going wrong?

Please post the error messages.
The IDE even provides a control to help you.

I've edited as per your recommendation.
Yes, I've already checked help in Arduino IDE, but the help wasn't enough.

Try commenting-out the second #include there

(I don't have any of these libraries)

Do you really need both these libraries? It doesn't appear that you are using both of them in your sketch.

I will need to work with a small database in firebase

Please provide a more detailed explanation of why you need both these libraries. Keep in mind that, though we are knowledgeable in the general subject matters covered by Arduino, we don't necessarily know anything about these specific libraries or even about firebase.

Please post a link (using the chain links icon on the forum toolbar to make it clickable) to where you downloaded the libraries from. Or if you installed it using Library Manager (Sketch > Include Library > Manage Libraries in the Arduino IDE or Libraries > Library Manager in the Arduino Web Editor) then say so and state the full name of the library.

Delete the FirebaseEsp32 Library and solved.

Thank you for your help.

You're welcome. I'm very glad to hear the problem is solved.

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