Invalide auth token

hello everyone, i just created a project in blynk, i have scraped the program and uploaded it. but in the serial mode it says “invalid auth token” how do I solve it?

Thank you to all of you

Hey there.
Are you using blynk legacy or blynk iot ?

First of all, I thank you for responding to my question.

I use the blynk legacy application

Can you show me your sketch please ?


#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>

char auth[] = "s7yhrNPGoSThknv8iMXS_SlGkDe52lA4";

char ssid[] = "LAB TEIN";
char pass[] = "2020_teinlab";

void setup(){
  Blynk.begin (auth, ssid, pass, "", 8080);

void loop(){;

Are you using a local server ?

no, im using a regular server

Use Blynk.begin(auth, ssid, pass);

just that ? without using “” again ?

oke i will try it

I tried it, and it worked !!!

thank you mr.jonh93 for saving my project.

once again thank you

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Your welcome buddy.

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@Fandu_ilham please edit your post, using the pencil icon at the bottom, and add triple backticks at the beginning and end of your code so that it displays correctly.
Triple backticks look like this:


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ok mr. @PeteKnight
thank you for reminding me

Problem was you were using the new Blynk IOT server “” in your code for some reason, instead of the Legacy server “”.

lib version?