Trouble sending emails through Gmail SMTP with PHP

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1 
Hey everyone,

I'm stuck trying to use Gmail's SMTP server to send emails from my PHP script. When I run it, I get this annoying error:

> authentication failure [SMTP: SMTP server does no support authentication (code: 250, response: mx.google.com at your service, [98.117.99.235] SIZE 35651584 8BITMIME STARTTLS ENHANCEDSTATUSCODES PIPELINING)]

I've been messing with this for hours and can't figure it out. Here's a simplified version of my code:

<?php
require_once "EmailSender.php";

$sender = new EmailSender();
$sender->setFrom("[email protected]");
$sender->setTo("[email protected]");
$sender->setSubject("Quick hello");
$sender->setBody("Hey there! How's it going?");

$sender->setSmtpDetails("smtp.gmail.com", 587, "[email protected]", "mypassword");

$result = $sender->send();

if ($result->isError()) {
    echo "Oops: " . $result->getErrorMessage();
} else {
    echo "Email sent successfully!";
}
?>

Any ideas what I'm doing wrong? Thanks in advance for any help!
2

I’ve dealt with this headache before. The issue isn’t merely about SMTP settings but also involves Google’s enhanced security measures. In my case, I enabled 2-Step Verification on my account and generated an app-specific password for the PHP application; using that password instead of my regular one solved the problem. This method is more secure, especially since Google is phasing out less secure app access.

I also switched to using TLS by moving to port 465 and initializing encryption appropriately. These changes made the connection both secure and reliable. Hope this helps get your email sending working smoothly.

3

Have you considered using OAuth 2.0 for authentication instead? It’s more secure and recommended by Google. You’ll need to set up a project in the Google Developer Console, obtain client credentials, and implement the OAuth flow in your PHP script. It’s a bit more complex initially, but it solves many authentication issues and adheres to Google’s security standards.

If you prefer a simpler solution, you could try a third-party email service like SendGrid or Mailgun. They offer easy-to-use APIs and often have free tiers for low-volume sending. This approach can save you headaches with SMTP configuration and authentication problems.

Remember to check your spam folder too. Sometimes, even when emails are sent successfully, they might end up there due to various factors.

4

yo dude, i had the same issue! try enabling ‘Less secure app access’ in ur Gmail settings. also, double-check ur password - sometimes Google blocks logins from unfamiliar apps. if that don’t work, maybe use an app-specific password instead. good luck!