Nodemailer and GMail OAuth: Username and Password not accepted - node.js

Question

So i have the following codes:
const nodemailer = require("nodemailer");
const mailer = {
service: "gmail",
auth: {
type: "OAuth2",
user: "mailtester123123123#gmail.com",
clientId: "123123123123123123123123123123.apps.googleusercontent.com",
clientSecret: "krW123123123123123123RqEnS",
refreshToken: "1/SM-7f31231231231231231231231231231231231231231231231UzH",
accessToken: "ya29.1234568791231324564897894231324564697897ss3Ggi-TkWO4HSIZBqHiLpoIkT7H_Sgii4RQxyVJ0QjIfjKB5zk"
}
}
const transporter = nodemailer.createTransport(mailer);
transporter.sendMail({
to: "mailtester123123123#windowslive.com",
subject: "test",
text: "test"
});
But when i try to send email, it always give error as follow: Error: Invalid login: 535-5.7.8 Username and Password not accepted. Learn more at
535 5.7.8 https://support.google.com/mail/?p=BadCredentials f67-v6sm75536287pfe.75 - gsmtp
This is the full trace:
(node:25324) UnhandledPromiseRejectionWarning: Error: Invalid login: 535-5.7.8 Username and Password not accepted. Learn more at
535 5.7.8 https://support.google.com/mail/?p=BadCredentials f67-v6sm75536287pfe.75 - gsmtp
at SMTPConnection._formatError (D:\Sources\NodeJS\test\node_modules\nodemailer\lib\smtp-connection\index.js:606:19)
at SMTPConnection._actionAUTHComplete (D:\Sources\NodeJS\test\node_modules\nodemailer\lib\smtp-connection\index.js:1335:34)
at SMTPConnection._responseActions.push.str (D:\Sources\NodeJS\test\node_modules\nodemailer\lib\smtp-connection\index.js:1314:26)
at SMTPConnection._processResponse (D:\Sources\NodeJS\test\node_modules\nodemailer\lib\smtp-connection\index.js:762:20)
at SMTPConnection._onData (D:\Sources\NodeJS\test\node_modules\nodemailer\lib\smtp-connection\index.js:558:14)
at TLSSocket._socket.on.chunk (D:\Sources\NodeJS\test\node_modules\nodemailer\lib\smtp-connection\index.js:510:47)
at TLSSocket.emit (events.js:182:13)
at addChunk (_stream_readable.js:283:12)
at readableAddChunk (_stream_readable.js:264:11)
at TLSSocket.Readable.push (_stream_readable.js:219:10)
Any idea what happened and how to fix this? Thank you.

Answer 1

This error occurs when you are trying to access Google account and forget to switch on Google less security option. Do following changes:
https://myaccount.google.com/lesssecureapps?utm_source=google-account&utm_medium=web

Answer 2

I had this error and my mistake was that I was trying to give only this permission:
"https://www.googleapis.com/auth/gmail.send"
I fixed it by giving the full permissions:
"https://mail.google.com/"
I'm talking about the scopes used to generate the tokens on https://developers.google.com/oauthplayground/