Troubleshooting GMAIL SMTP authentication errors

Overview

Google's security settings block sending mail via SMTP through its servers unless you enable OAuth 2.0 authentication. This article points you to Google's and the WP Mail SMTP plugin's official instructions for enabling OAuth 2.0 (DreamHost support can't assist with this custom configuration).

Background

Many websites use PHP to send email via SMTP. For example, you could create a custom mail form or use a WordPress SMTP plugin:

• Send PHP mail via SMTP
• PHPmailer overview
• Configuring the 'WP Mail SMTP' plugin with Gmail

Unfortunately, Google's security settings do not allow you to send mail via SMTP through their servers unless you explicitly allow it. The following instructions show you how to do that with OAuth 2.0 instead.

How do I enable the OAuth 2.0 protocol?

You can enable OAuth 2.0 to authenticate connections. See the following pages for more information:

• Google authentication and authorization
• Enabling the OAuth 2 API to use with your WordPress Mail SMTP plugin

Please note that DreamHost support is unable to assist with this custom configuration.

See also

• Email troubleshooting checklist for escalation
• Google Workspace overview
• Google Workspace FAQs
• Managing your Google Workspace Account
• Migrating email to Google Workspace