Securely Send WordPress Emails Gmail WP Mail SMTP

I have been using the WP Mail STMP WordPress plugin to send email from WordPress using either a STMP relay service and more recently Office 365. However, I was curious if you could use something for free. I went to research and noticed the plugin had an option for Gmail. I found an article that explained how to configure.

Here are the steps I did:

Register in Gmail
- https://www.google.com/accounts/Logout?continue=https://console.developers.google.com/start/api?id=gmail
- Click Yes and click Agree and continue
- Click “Go to credentials”
- Credentials
  - Which API are you using – Gmail API
  - Where will you be calling the API from – Web server
  - What data will you be accessing – User data
  - Click “What credentials do I need”
- OAuth 2.0 client ID
  - Name – name
  - Authorized JavaScript origins
    - http://domainname.com/
  - Authorized redirect URIs
    - Copy from plugin settings page
      - http://domainname.com/wp-admin/options-general.php?page=wp-mail-smtp&tab=auth
  - Click “Create client ID”
  - Product Name – name
  - Click Continue
  - Click “I’ll do this later”
  - Edit to see entire I
Copy Client ID and Client secret into WordPress plugin
- Save and page will refresh
- Click “Allow plugin to send emails using your Google account”
  - Enter Gmail address and password
  - If app isn’t verified, go to advanced
  - Allow
Confirm in plugin that everything was successfully linked
- Test email in plugin