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Nodemailer is not working on production with NodeJS and gmail [duplicate]

I try to use nodemailer to implement a contact form using NodeJS but it works only on local it doesn't work on a remote server...
My error message :
[website.fr-11 (out) 2013-11-09T15:40:26] { [AuthError: Invalid login - 534-5.7.14 <https://accounts.google.com/ContinueSignIn?sarp=1&scc=1&plt=AKgnsbvlX
[website.fr-11 (out) 2013-11-09T15:40:26] 534-5.7.14 V-dFQLgb7aRCYApxlOBuha5ESrQEbRXK0iVtOgBoYeARpm3cLZuUS_86kK7yPis7in3dGC
[website.fr-11 (out) 2013-11-09T15:40:26] 534-5.7.14 N1sqhr3D2IYxHAN3m7QLJGukwPSZVGyhz4nHUXv_ldo9QfqRydPhSvFp9lnev3YQryM5TX
[website.fr-11 (out) 2013-11-09T15:40:26] 534-5.7.14 XL1LZuJL7zCT5dywMVQyWqqg9_TCwbLonJnpezfBLvZwUyersknTP7L-VAAL6rhddMmp_r
[website.fr-11 (out) 2013-11-09T15:40:26] 534-5.7.14 A_5pRpA> Please log in via your web browser and then try again.
[website.fr-11 (out) 2013-11-09T15:40:26] 534-5.7.14 Learn more at https://support.google.com/mail/bin/answer.py?answer=787
[website.fr-11 (out) 2013-11-09T15:40:26] 534 5.7.14 54 fr4sm15630311wib.0 - gsmtp]
[website.fr-11 (out) 2013-11-09T15:40:26] name: 'AuthError',
[website.fr-11 (out) 2013-11-09T15:40:26] data: '534-5.7.14 <https://accounts.google.com/ContinueSignIn?sarp=1&scc=1&plt=AKgnsbvlX\r\n534-5.7.14 V-dFQLgb7aRCYApxlOBuha5ESrQEbRXK0iVtOgBoYeARpm3cLZuUS_86kK7yPis7in3dGC\r\n534-5.7.14 N1sqhr3D2IYxHAN3m7QLJGukwPSZVGyhz4nHUXv_ldo9QfqRydPhSvFp9lnev3YQryM5TX\r\n534-5.7.14 XL1LZuJL7zCT5dywMVQyWqqg9_TCwbLonJnpezfBLvZwUyersknTP7L-VAAL6rhddMmp_r\r\n534-5.7.14 A_5pRpA> Please log in via your web browser and then try again.\r\n534-5.7.14 Learn more at https://support.google.com/mail/bin/answer.py?answer=787\r\n534 5.7.14 54 fr4sm15630311wib.0 - gsmtp',
[website.fr-11 (out) 2013-11-09T15:40:26] stage: 'auth' }
My controller :
exports.contact = function(req, res){
var name = req.body.name;
var from = req.body.from;
var message = req.body.message;
var to = '*******#gmail.com';
var smtpTransport = nodemailer.createTransport("SMTP",{
service: "Gmail",
auth: {
user: "******#gmail.com",
pass: "*****"
}
});
var mailOptions = {
from: from,
to: to,
subject: name+' | new message !',
text: message
}
smtpTransport.sendMail(mailOptions, function(error, response){
if(error){
console.log(error);
}else{
res.redirect('/');
}
});
}

I solved this by going to the following url (while connected to google with the account I want to send mail from):
https://www.google.com/settings/security/lesssecureapps
There I enabled less secure apps.
Done

See nodemailer's official guide to connecting Gmail:
https://community.nodemailer.com/using-gmail/
-
It works for me after doing this:
Enable less secure apps - https://www.google.com/settings/security/lesssecureapps
Disable Captcha temporarily so you can connect the new device/server - https://accounts.google.com/b/0/displayunlockcaptcha

Easy Solution:
var nodemailer = require('nodemailer');
var smtpTransport = require('nodemailer-smtp-transport');
var transporter = nodemailer.createTransport(smtpTransport({
service: 'gmail',
host: 'smtp.gmail.com',
auth: {
user: 'somerealemail#gmail.com',
pass: 'realpasswordforaboveaccount'
}
}));
var mailOptions = {
from: 'somerealemail#gmail.com',
to: 'friendsgmailacc#gmail.com',
subject: 'Sending Email using Node.js[nodemailer]',
text: 'That was easy!'
};
transporter.sendMail(mailOptions, function(error, info){
if (error) {
console.log(error);
} else {
console.log('Email sent: ' + info.response);
}
});
Step 1:
go here https://myaccount.google.com/lesssecureapps and enable for less secure apps. If this does not work then
Step 2
go here https://accounts.google.com/DisplayUnlockCaptcha and enable/continue and then try.
for me step 1 alone didn't work so i had to go to step 2.
i also tried removing the nodemailer-smtp-transport package and to my surprise it works. but then when i restarted my system it gave me same error, so i had to go and turn on the less secure app (i disabled it after my work).
then for fun i just tried it with off(less secure app) and vola it worked again!

You should use an XOAuth2 token to connect to Gmail. No worries, Nodemailer already knows about that:
var smtpTransport = nodemailer.createTransport('SMTP', {
service: 'Gmail',
auth: {
XOAuth2: {
user: smtpConfig.user,
clientId: smtpConfig.client_id,
clientSecret: smtpConfig.client_secret,
refreshToken: smtpConfig.refresh_token,
accessToken: smtpConfig.access_token,
timeout: smtpConfig.access_timeout - Date.now()
}
}
};
You'll need to go to the Google Cloud Console to register your app. Then you need to retrieve access tokens for the accounts you wish to use. You can use passportjs for that.
Here's how it looks in my code:
var passport = require('passport'),
GoogleStrategy = require('./google_oauth2'),
config = require('../config');
passport.use('google-imap', new GoogleStrategy({
clientID: config('google.api.client_id'),
clientSecret: config('google.api.client_secret')
}, function (accessToken, refreshToken, profile, done) {
console.log(accessToken, refreshToken, profile);
done(null, {
access_token: accessToken,
refresh_token: refreshToken,
profile: profile
});
}));
exports.mount = function (app) {
app.get('/add-imap/:address?', function (req, res, next) {
passport.authorize('google-imap', {
scope: [
'https://mail.google.com/',
'https://www.googleapis.com/auth/userinfo.email'
],
callbackURL: config('web.vhost') + '/add-imap',
accessType: 'offline',
approvalPrompt: 'force',
loginHint: req.params.address
})(req, res, function () {
res.send(req.user);
});
});
};

Worked fine:
1- install nodemailer, package if not installed
(type in cmd) : npm install nodemailer
2- go to https://myaccount.google.com/lesssecureapps and turn on Allow less secure apps.
3- write code:
var nodemailer = require('nodemailer');
var transporter = nodemailer.createTransport({
service: 'gmail',
auth: {
user: 'trueUsername#gmail.com',
pass: 'truePassword'
}
});
const mailOptions = {
from: 'any#any.com', // sender address
to: 'true#true.com', // list of receivers
subject: 'test mail', // Subject line
html: '<h1>this is a test mail.</h1>'// plain text body
};
transporter.sendMail(mailOptions, function (err, info) {
if(err)
console.log(err)
else
console.log(info);
})
4- enjoy!

I had the same problem. Allowing "less secure apps" in my Google security settings made it work!

Non of the above solutions worked for me. I used the code that exists in the documentation of NodeMailer. It looks like this:
let transporter = nodemailer.createTransport({
host: 'smtp.gmail.com',
port: 465,
secure: true,
auth: {
type: 'OAuth2',
user: 'user#example.com',
serviceClient: '113600000000000000000',
privateKey: '-----BEGIN PRIVATE KEY-----\nMIIEvgIBADANBg...',
accessToken: 'ya29.Xx_XX0xxxxx-xX0X0XxXXxXxXXXxX0x',
expires: 1484314697598
}
});

Same problem happened to me too. I tested my system on localhost then deployed to the server (which is located at different country) then when I try the system on production server I saw this error. I tried these to fix it:
https://www.google.com/settings/security/lesssecureapps Enabled it but it was not my solution
https://g.co/allowaccess I allowed access from outside for a limited time and this solved my problem.

I found the simplest method, described in this article mentioned in Greg T's answer, was to create an App Password which is available after turning on 2FA for the account.
myaccount.google.com > Sign-in & security > Signing in to Google > App Passwords
This gives you an alternative password for the account, then you just configure nodemailer as a normal SMTP service.
var smtpTransport = nodemailer.createTransport({
host: "smtp.gmail.com",
port: 587,
auth: {
user: "username#gmail.com",
pass: "app password"
}
});
While Google recommend Oauth2 as the best option, this method is easy and hasn't been mentioned in this question yet.
Extra tip: I also found you can add your app name to the "from" address and GMail does not replace it with just the account email like it does if you try to use another address. ie.
from: 'My Pro App Name <username#gmail.com>'

It is resolved using nodemailer-smtp-transport module inside createTransport.
var smtpTransport = require('nodemailer-smtp-transport');
var transport = nodemailer.createTransport(smtpTransport({
service: 'gmail',
auth: {
user: '*******#gmail.com',
pass: '*****password'
}
}));

Many answers advice to allow less secure apps which is honestly not a clean solution.
Instead you should generate an app password dedicated to this use:
Log in to your Google account
Go to security
Under Signing in to Google enable 2-Step Verification
Under Signing in to Google click on App passwords.
You'll now generate a new password. Select the app as Mail and the device as Other (Custom name) and name it.
Save the app password
You can now use this app password instead of your log in password.

Try disabling captchas in your gmail account; probably being triggered based on IP address of requestor.
See: How to use GMail as a free SMTP server and overcome captcha

For me is working this way, using port and security (I had issues to send emails from gmail using PHP without security settings)
I hope will help someone.
var sendEmail = function(somedata){
var smtpConfig = {
host: 'smtp.gmail.com',
port: 465,
secure: true, // use SSL,
// you can try with TLS, but port is then 587
auth: {
user: '***#gmail.com', // Your email id
pass: '****' // Your password
}
};
var transporter = nodemailer.createTransport(smtpConfig);
// replace hardcoded options with data passed (somedata)
var mailOptions = {
from: 'xxxx#gmail.com', // sender address
to: 'yyyy#gmail.com', // list of receivers
subject: 'Test email', // Subject line
text: 'this is some text', //, // plaintext body
html: '<b>Hello world ✔</b>' // You can choose to send an HTML body instead
}
transporter.sendMail(mailOptions, function(error, info){
if(error){
return false;
}else{
console.log('Message sent: ' + info.response);
return true;
};
});
}
exports.contact = function(req, res){
// call sendEmail function and do something with it
sendEmail(somedata);
}
all the config are listed here (including examples)

If you use Express, express-mailerwrapsnodemailervery nicely and is very easy to use:
//# config/mailer.js
module.exports = function(app) {
if (!app.mailer) {
var mailer = require('express-mailer');
console.log('[MAIL] Mailer using user ' + app.config.mail.auth.user);
return mailer.extend(app, {
from: app.config.mail.auth.user,
host: 'smtp.gmail.com',
secureConnection: true,
port: 465,
transportMethod: 'SMTP',
auth: {
user: app.config.mail.auth.user,
pass: app.config.mail.auth.pass
}
});
}
};
//# some.js
require('./config/mailer.js)(app);
app.mailer.send("path/to/express/views/some_view", {
to: ctx.email,
subject: ctx.subject,
context: ctx
}, function(err) {
if (err) {
console.error("[MAIL] Email failed", err);
return;
}
console.log("[MAIL] Email sent");
});
//#some_view.ejs
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title><%= subject %></title>
</head>
<body>
...
</body>
</html>

For some reason, just allowing less secure app config did not work for me even the captcha thing. I had to do another step which is enabling IMAP config:
From google's help page: https://support.google.com/mail/answer/7126229?p=WebLoginRequired&visit_id=1-636691283281086184-1917832285&rd=3#cantsignin
In the top right, click Settings Settings.
Click Settings.
Click the Forwarding and POP/IMAP tab.
In the "IMAP Access" section, select
Enable IMAP.
Click Save Changes.

all your code is okay only the things left is just go to the link https://myaccount.google.com/security
and keep scroll down and you will found Allow less secure apps: ON and keep ON, you will find no error.

Just add "host" it will work .
host: 'smtp.gmail.com'
Then enable "lesssecureapps" by clicking bellow link
https://myaccount.google.com/lesssecureapps

Google has disabled the Less Secure App Access, Below is New Process to use Gmail in Nodejs
Now you have to enable 2 Step Verification in Google (How to Enable 2 Step Auth)
You need to generate App Specific Password. Goto Google My Account > Security
Click on App Password > Select Other and you will get App Password
You can use normal smtp with email and App password.

exports.mailSend = (res, fileName, object1, object2, to, subject, callback)=> {
var smtpTransport = nodemailer.createTransport('SMTP',{ //smtpTransport
host: 'hostname,
port: 1234,
secureConnection: false,
// tls: {
// ciphers:'SSLv3'
// },
auth: {
user: 'username',
pass: 'password'
}
});
res.render(fileName, {
info1: object1,
info2: object2
}, function (err, HTML) {
smtpTransport.sendMail({
from: "mail#from.com",
to: to,
subject: subject,
html: HTML
}
, function (err, responseStatus) {
if(responseStatus)
console.log("checking dta", responseStatus.message);
callback(err, responseStatus)
});
});
}
You must add secureConnection type in you code.

I was using an old version of nodemailer 0.4.1 and had this issue. I updated to 0.5.15 and everything is working fine now.
Edited package.json to reflect changes then
npm install

Just attend those:
1- Gmail authentication for allow low level emails does not accept before you restart your client browser
2- If you want to send email with nodemailer and you wouldnt like to use xouath2 protocol there you should write as secureconnection:false like below
const routes = require('express').Router();
var nodemailer = require('nodemailer');
var smtpTransport = require('nodemailer-smtp-transport');
routes.get('/test', (req, res) => {
res.status(200).json({ message: 'test!' });
});
routes.post('/Email', (req, res) =>{
var smtpTransport = nodemailer.createTransport({
host: "smtp.gmail.com",
secureConnection: false,
port: 587,
requiresAuth: true,
domains: ["gmail.com", "googlemail.com"],
auth: {
user: "your gmail account",
pass: "your password*"
}
});
var mailOptions = {
from: 'from#gmail.com',
to:'to#gmail.com',
subject: req.body.subject,
//text: req.body.content,
html: '<p>'+req.body.content+' </p>'
};
smtpTransport.sendMail(mailOptions, (error, info) => {
if (error) {
return console.log('Error while sending mail: ' + error);
} else {
console.log('Message sent: %s', info.messageId);
}
smtpTransport.close();
});
})
module.exports = routes;

first install nodemailer
npm install nodemailer --save
import in to js file
const nodemailer = require("nodemailer");
const smtpTransport = nodemailer.createTransport({
service: "Gmail",
auth: {
user: "example#gmail.com",
pass: "password"
},
tls: {
rejectUnauthorized: false
}
});
const mailOptions = {
from: "example#gmail.com",
to: sending#gmail.com,
subject: "Welcome to ",
text: 'hai send from me'.
};
smtpTransport.sendMail(mailOptions, function (error, response) {
if (error) {
console.log(error);
}
else {
console.log("mail sent");
}
});
working in my application

You may need to "Allow Less Secure Apps" in your Gmail account (it's all the way at the bottom). You also may need to "Allow access to your Google account".
You also may need to "Allow access to your Google account".

This is my Nodemailer configuration which worked after some research.
Step 1: Enable lesssecureapp
https://www.google.com/settings/security/lesssecureapps
Step 2: The Nodemailer configuration for Gmail
Setting up the transporter : A transporter is going to be an object that can send mail. It is the transport configuration object, connection URL, or a transport
plugin instance
let transporter = nodemailer.createTransport({
service: 'gmail', // the service used
auth: {
user: process.env.EMAIL_FROM, // authentication details of sender, here the details are coming from .env file
pass: process.env.EMAIL_FROM_PASSWORD,
},
});
Writing the message
const message = {
from: 'myemail#gmail.com', // sender email address
to: "receiver#example.com, receiver2#gmail.com", // reciever email address
subject: `The subject goes here`,
html: `The body of the email goes here in HTML`,
attachments: [
{
filename: `${name}.pdf`,
path: path.join(__dirname, `../../src/assets/books/${name}.pdf`),
contentType: 'application/pdf',
},
],
Sending the mail
transporter.sendMail(message, function (err, info) {
if (err) { // if error
console.log(err);
} else {
console.log(info); // if success
}
});

I also had issues with nodemailer email sending when running on Vercel lambda in production.
What fixed it in my case was to await for sendMail Promise to resolve.
I also added nodemailer-smtp-transport like suggested in this thread but I don't think it made a difference.
Here is my whole function:
const nodemailer = require('nodemailer');
const smtpTransport = require('nodemailer-smtp-transport');
const transporter = nodemailer.createTransport(smtpTransport({
service: 'gmail',
auth: {
user: '***#gmail.com',
pass: process.env.SMTP_PASSWORD,
},
}));
async function contact(req: any, res: any) {
try {
const response = await transporter.sendMail({
from: '"*** <***gmail.com>', // sender address
to: "***#gmail.com", // list of receivers
subject: `***`, // Subject line
html: `${req.body.message}<br/><br/>${req.body.firstname} ${req.body.lastname} - <b>${req.body.email}</b>`, // html body
});
} catch (error: any) {
console.log(error);
return res.status(error.statusCode || 500).json({ error: error.message });
}
return res.status(200).json({ error: "" });
}
export default contact;

As pointed out by Yaach, as of May 30th, 2022, Google no longer supports Less Secure Apps, and instead switched over to their own Gmail API.

Here is the sample code for Gmail SMTP with nodemailer.
"use strict";
const nodemailer = require("nodemailer");
async function main() {
let transporter = nodemailer.createTransport({
host: "smtp.gmail.com",
transportMethod: "SMTP",
secureConnection: true,
port: 465,
secure: true, // upgrade later with STARTTLS
auth: {
user: "yourEmail#gmail.com",
pass: "Your App Specific password",
},
});
let info = await transporter.sendMail(
{
from: "yourEmail#gmail.com",
to: "to#gmail.com",
subject: "Testing Message Message",
text: "I hope this message gets delivered!",
html: "<b>Hello world?</b>", // html body
},
(err, info) => {
if (err) {
console.log(err);
} else {
console.log(info.envelope);
console.log(info.messageId);
}
}
);
}
main();

Less secure option is not supported anymore by gmail.
For sending email from third party, gmail is also not allowing with its user password.
You should now use App Password to resolve this issue.
Hope this link will help to set your app password.
https://support.google.com/mail/answer/185833?hl=en

There is another option to use SendGrid for email delivery with no failure. A lot of the time, Nodemailer gives failure for mail which could happen frequently.
Nodemailer can be found in the link.

Possible issue when sending email with SMTP.js

I am using smtp.js to send mails to my email id whose credentials i made using smtp.js.I made a contact form where i want the user to enter his info and email and that should be sent to my email.So according to this logic, my mail should be in To property and sender's mail should be in the From property.However, when i run the code, it throws an error as
"Mailbox name not allowed. The server response was: Envelope FROM 'sendername#gmail.com' email address not allowed.".
If not possible,can u tell me some other alternative using js.Thanks
Code:
function sendmail()
{
var name = $('#name').val();
var email = $('#email').val();
var phone = $('#phone').val();
var address = $('#address').val();
var postal = $('#postal').val();
console.log(typeof(email))
// var body = $('#body').val();
var Body='Subject: '+"Estimated Quote"+'<br>Name: '+name+'<br>Email: '+email+'<br>Phone: '+phone+'<br>Address: '+address+'<br>Postal Code: '+postal+'<br>Quote exl VAT: '+vat_excl+'<br>Quote incl VAT: '+vat_incl;
//console.log(name, phone, email, message);
Email.send({
SecureToken:"2d019ac3-046b-4c4f-94e2-f4f3bf08fb1f",
To: 'receivermail#gmail.com',
From: email,
Subject: "New mail from "+name,
Body: Body
}).then(
message =>{
console.log (message);
if(message=='OK'){
alert('Thanks for submitting details.We will contact you soon.');
}
else{
console.error (message);
alert('Error submitting form.')
}

I don't know which library are you using to stablish the SMTP connection, but first of all make sure that the SMTP sever accepts all the domains that you're requiring.
I'd suggest you to use nodemailer which is fairly easy to use.
Example:
// CONFIG SETUP
import { createTransport } from 'nodemailer';
const Transporter = createTransport({
host: process.env.SMTP_HOST || 'localhost',
port: Number(process.env.SMTP_PORT) || 25,
secure: false,
tls: { rejectUnauthorized: false }, // THIS WILL BE ACCORDING TO YOUR SMTP CONFIG
});
// EXAMPLE OF USAGE
const info = Transporter.sendMail({
from: 'sender#test.com',
to: 'to#test.com',
subject: 'TEST',
text: 'TEST',
});

Email sent but not recieved, I'm using nodemailer

I'm using nodemailer v^6.4.17 and I'm having trouble getting it to send emails. I do not get the issue cause in the console, it is showing that the emails has been sent. But when I go to client side and check inbox, I don't see the email.
let transporter = nodemailer.createTransport({
name: 'www.example.com',
host: '******************',
port: 465,
secure: true,
auth: {
user: ''sender#email.com'',
pass: '**********',
},
});
let info = await transporter.sendMail({
from: 'sender#email.com',
to: "reciever#email.com",
subject: "Hi",
text: "Hello world!",
html: '<h1>2021</h1>',
});
What I'm I missing here? Thanks.

Make sure you enable the less secure app in your Gmail account.
enable your Gmail account less secure app
Also, make sure to check email in spam emails.

Try doing it like this -
var mailOptions = {
from: "----------",
to: "-------",
subject: "------------",
text: "------------",
html: "-----------"
};
smtpTransport.sendMail(mailOptions, function (error, response) {
if (error) {
console.log(error);
console.log("Cannot connect to SMTP server right now");
} else {
console.log("Success" + response);
}
});

How can I send emails from a user's account using Node.js?

i'm working in a program that saves contacts. I want to add a new fuction that lets you send emails to your contacts form your email account.
I tried to do it with nodemailer, taking the login data from a form that users need to fill in.
But nodemailer sends me a error, look this:
Error: Invalid login: 535-5.7.8 Username and Password not accepted.
I tried with applcation password and activating the less secure option, but the error continues. Look my code:
Here i take the user's email and password:
router.post('/email', isLoggedIn, async (req, res) => {
var { email } = req.body;
var { password } = req.body;
var parts = email.substring(email.lastIndexOf('#')+ 1);
exports.email = email;
exports.password = password;
res.redirect('/links/message')
});
Here i take de message:
router.post('/sendmessage', isLoggedIn, async (req, res) => {
const { message } = req.body;
const { assumpt } = req.body;
exports.message = message;
exports.assumpt = assumpt;
res.redirect('/links/contactsemail')
});
Finally, i take the category contact that you need to send the email and i send the email with the message and data login that users give me:
router.post('/contactsend', isLoggedIn, async (req, ress) => {
const { contacts } = req.body;
const row = await pool.query('SELECT count(email) AS email FROM links WHERE user_id=? AND category=? AND email IS NOT NULL',[req.user.id, contacts]);
const rows = row[0].email;
const assumpt = myModule.assumpt;
const message = myModule.message;
const email = myModule.email;
const password = myModule.password
var parts = email.substring(email.lastIndexOf('#')+ 1);
const hosts = 'smtp.' + parts;
var transporter = nodemailer.createTransport({
host: hosts,
port: 587,
auth: {
user: email,
pass: password
}
});
for (i = 1; i <= rows; i++ ){
var email1 = await pool.query('SELECT email AS email FROM (SELECT email, ROW_NUMBER() OVER (ORDER BY email) AS rn FROM links WHERE user_id= ? AND category=?) q WHERE rn = ?', [req.user.id, contacts, i]);
var email1 = email1[0].email;
var mailOptions = {
from: email,
to: email1,
subject: assumpt,
text: message
};
transporter.sendMail(mailOptions, function (error, info) {
if (error) {
console.log(error);
} else {
console.log('Email sent: ' + info.response);
res.flash('success', 'Missatge enviat correctament');
res.redirect('/links');
}
});
};
});
My questions are:
How can I fix the error?
I can do it in different way that's it's easier and better?

Am I understanding this correctly that you want your users to enter their credentials for their private/external e-mail provider so you can send an e-mail using that provider?
In that case there is no generic answer to your question since the specifics of the required configuration highly depends on the e-mail provider. For example in your code:
var parts = email.substring(email.lastIndexOf('#')+ 1);
const hosts = 'smtp.' + parts;
var transporter = nodemailer.createTransport({
host: hosts,
port: 587,
auth: {
user: email,
pass: password
}
});
This block already has some hard-coded assumptions, i.e. that the smtp host for john.doe#example.net is smtp.example.org and that the username for that e-mail is also john.doe#example.net which - both - is not necessarily the case for many e-mail providers.
So even if this would work for you it is very likely it won't work for all of your users!
Instead you should use a single smtp gateway/relay your application can forward e-mails to. Then you also won't need the credentials of the users themselves but can use the login credentials for your application to that smtp gateway.
But it depends on the configuration of your smtp gateway whether you'll be allow to send with arbitrary sender addresses. And even if your gateway might allow this the mails may be blocked due to spam filters since your gateway may not be allowed to send e-mails for the users' domain, see SPF.
Therefor I would advise you - besides using a dedicated smtp gateway - to send with an e-mail address/domain you own and control. You may still augment the mail coming directly from the user, e.g. by setting the display name and Reply-To header appropriately:
From: "John Doe" <myapp#example.com>
To: jane.doe#example.org
Reply-To: "John Doe" <john.doe#example.org>
Subject: "A message from John Doe via MyApp"
For this mail the recipient would get the sending user's name displayed as sender (but your app's e-mail and not the user's) and when hitting the reply button the reply would by default - depending on the e-mail client - be sent back to the user, i.e. in this case john.doe#example.org.

Nodejs nodemailer error

Running Nodemailer results in the following error, then what should I do to fix it?
Error: Missing credentials for "PLAIN"
at SMTPConnection._formatError
var nodemailer=require('nodemailer');
var transporter = nodemailer.createTransport({
service:'Gmail',
auth:{
user:'kumaresankeerthy#gmail.com',
password:'9943886854**'
}
});
var mailOptions={
};
transporter.sendMail(mailOptions,function(error,info){
if(error){
console.log(error);
} else{
console.log('email sent:' +info.response);
}
});

You are giving wrong arguments in the constructor. Its pass not password
As per official docs
let transporter = nodemailer.createTransport({
host: 'smtp.ethereal.email',
port: 587,
secure: false, // true for 465, false for other ports
auth: {
user: account.user, // generated ethereal user
pass: account.pass // generated ethereal password
}
});

solved this by going to the following url (while connected to google with the account I want to send mail from):
https://www.google.com/settings/security/lesssecureapps*
you have enable less secure app in your gmail after that it will; work

You need to set up the transporter differently, using the actual email and password of a real Google Account.
// create reusable transporter object using the default SMTP transport
let transporter = nodemailer.createTransport({
service: 'gmail',
auth: {
user: 'somerealemailaddress#gmail.com', //email address to send from
pass: 'somerealemailpassword' //the actual password for that account
}
});