How do I fix 535 incorrect authentication?

Methods To Resolve “SMTP Error 535 Authentication Failed” Message

  1. Firstly, you should log in to your control panel and check your current account status.
  2. Check the username and password provided to log in to your mail server.
  3. Block the IP addresses that are consistently trying to log in to your account.

What is SMTP error could not authenticate?

“smtp error: could not authenticate” is a common error when users send emails via PHPMailer using SMTP authentication. This error occurs when the application can’t establish an SMTP connection to the mail server.

What does code 535 mean?

A “Server says: 535 – Incorrect authentication data” error is usually related to the SMTP User Authentication details you have configured (or not configured) in your email settings.

What is 535 Invalid user ID or password?

This error can have two meanings: The username and password that you have entered into your program are incorrect and you are failing authentication. Your account has been disabled because of a problem. You are using IP based authentication and your account has been disabled or has expired (uncommon)

Why is SMTP not working?

Check whether there is network access from CSO to the SMTP server. Check whether the firewall is blocking SMTP traffic to SMTP server or whether the ports are blocked. If the server settings and authentication settings are correct, check whether the firewall is blocking port 587 and 465 and SMTP traffic.

How do I fix failed to authenticate SMTP server with Username?

Error “Failed to authenticate on SMTP server with username” – Causes & fixes

  1. Sender’s IP blocked.
  2. Wrong config file or PHP settings.
  3. Firewall blocks outgoing mail.
  4. Connection allowed only via SSL/TLS protocol.
  5. Expired password.
  6. Wrong SMTP port (25 / 587 / 456)
  7. Google blocks insecure access.

How does SMTP authentication work?

SMTP Authentication is the mechanism by which the clients of an ISP identify themselves to the mail server through which they intend to send email. It is not possible for any person to send email via any mail server they choose; mail servers will only allow the sending of email by legitimate users.