Description
Web357 SMTP Connect for Gmail does exactly one thing: it delivers your WordPress email through your own Gmail or Google Workspace mailbox over OAuth 2.0 (XOAUTH2). It is not a multi-provider mailer — there is no provider dropdown and no SMTP password field.
Why another SMTP plugin?
The directory already has plenty of general-purpose mailers, and if you need to switch between SendGrid, Mailgun, Amazon SES, Postmark and Gmail, one of those is the better tool. This plugin is built for the site owner who has already decided on Gmail or Google Workspace and wants that one path done properly. Four things follow from that decision:
1. OAuth 2.0 is the only authentication path — deliberately.
Most general SMTP plugins accept a Google 16-character App Password because it is the quickest route to a working setup. That password is a long-lived credential stored in plain text in wp_options; anyone with database read access can send mail as you, and Google has been steadily restricting App Password issuance. This plugin has no password field at all. You authorise once through Google’s consent screen, the plugin stores a refresh token scoped to your own Google Cloud OAuth client, and it renews the short-lived access token itself. Revoking access in your Google Account instantly kills the site’s ability to send — something an App Password cannot give you.
2. Your OAuth client, your Google Cloud project.
You create the Client ID and Secret in your own Google Cloud Console project. The plugin never brokers the connection through a Web357-owned OAuth app, so consent screens, scopes and quota all belong to you and survive independently of this plugin.
3. Nothing is routed through anyone else’s servers.
Your site talks directly to accounts.google.com, oauth2.googleapis.com and smtp.gmail.com. There is no Web357 relay, no analytics endpoint, no phone-home. Message bodies, recipients and headers never leave the path between your server and Google.
4. It hooks pre_wp_mail, and that is the whole footprint.
No replacement of core PHPMailer classes, no admin dashboard widgets, no cron jobs, no database writes on the send path. The plugin registers one filter and hands the message to WordPress’s own bundled PHPMailer with XOAUTH2 configured. On a WooCommerce checkout that means the mail path adds a token check and an SMTP handshake, and nothing else.
Transport settings are fixed to what Gmail actually accepts for XOAUTH2 — smtp.gmail.com on port 587 with STARTTLS and full certificate verification. There are no encryption, port or “disable SSL verification” toggles, because every other combination either fails against Gmail or weakens the connection that carries your access token.
Full setup, Google Cloud OAuth registration, and troubleshooting steps are in the official documentation.
Features
- OAuth 2.0 (XOAUTH2) authentication against your own Google Cloud OAuth client, with automatic access-token refresh.
- Reroutes every
wp_mail()call through your Gmail or Google Workspace mailbox. - Built-in Test Email tool that sends a real message from the admin and reports the exact failure reason when it does not arrive.
- Authorized Redirect URI helper with one-click copy, so the value you paste into Google Cloud Console matches character for character.
- One-click revoke that deletes the stored tokens from your site.
- Works with WooCommerce, Contact Form 7, WPForms, Fluent Forms, Gravity Forms, MemberPress, LearnDash, and anything else that calls
wp_mail(). - Translation-ready, no external assets, no tracking.
External services
This plugin connects to Google’s identity and mail services so it can send WordPress emails through your Gmail or Google Workspace mailbox using OAuth 2.0. It requires a Google Cloud project and OAuth Client ID/Secret that you create and control.
Google’s identity platform (accounts.google.com, oauth2.googleapis.com) is used to authorize the plugin against your Google account and to exchange/refresh the resulting access token. When you click “Authenticate with Gmail” in the Configuration tab, and again automatically whenever a stored access token is near expiry, the plugin sends your app’s Client ID, Client Secret, redirect URI, and the OAuth authorization code or refresh token, and receives back an access token and refresh token in return. Right after you authorize, it also calls Google’s https://www.googleapis.com/oauth2/v3/userinfo endpoint once to read the connected account’s email address.
Terms of use: https://policies.google.com/terms — Privacy statement: https://policies.google.com/privacy
Gmail’s SMTP server (smtp.gmail.com) is used to actually send every outgoing email — the message subject, body, recipient addresses, headers, and attachments — authenticated via OAuth 2.0 (XOAUTH2), not a stored password. This happens every time WordPress (or any plugin using wp_mail()) sends an email, and when you use the built-in Test Email tool.
Sending mail over Gmail’s SMTP with OAuth requires Google’s full-account mail scope (https://mail.google.com/) rather than a narrower “send only” scope — this is a constraint of Gmail’s SMTP+XOAUTH2 authentication itself, not a plugin choice. The plugin only ever uses this access to send the emails WordPress generates; it does not read, modify, or delete anything in your mailbox.
No data is sent to Google until you complete the OAuth connection yourself.
Screenshots



Installation
Your site must use HTTPS. Google OAuth 2.0 will not complete on a plain HTTP site.
- In WordPress, go to Plugins > Add New Plugin > Upload Plugin and select the
web357-smtp-connect-for-gmail.zipfile. (Or unzip it and upload theweb357-smtp-connect-for-gmailfolder to/wp-content/pluginsvia FTP.) - Activate the plugin.
- Open Settings > SMTP Connect for Gmail.
- Follow the configuration guide to create a Google Cloud OAuth app, paste your Client ID and Client Secret, and click Authenticate with Gmail.
- Send a test email from the Configuration tab to confirm delivery.
FAQ
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Does it need a Google App Password?
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No, and it will not accept one. There is no password field anywhere in the plugin. Authentication is Google’s OAuth 2.0 consent flow using an OAuth client you create in your own Google Cloud project. Your site stores a refresh token, not a credential that can be replayed as a password.
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Why can I not change the SMTP port, encryption or From Name?
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Gmail’s XOAUTH2 endpoint accepts
smtp.gmail.comon port 587 with STARTTLS; the alternatives either fail or downgrade the connection that carries your access token, so they are fixed rather than exposed as settings you can get wrong. The From address is fixed too, but by Google: its anti-spoofing rules require the envelope sender to be the authenticated mailbox, so any other value would be rewritten or rejected on Google’s side. Setting a different display name is a Gmail account setting (“Send mail as”), and changing it there applies to every message the mailbox sends, including these. -
Is any feature locked, limited, or reserved for a paid version?
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No. Everything the plugin can do is in this package and works after you connect your account.
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Does any of my email go through Web357’s servers?
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No. Your server connects directly to Google. The plugin makes no requests to any Web357 endpoint and collects no telemetry.
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Does it work with personal Gmail and Google Workspace accounts?
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Yes, both — personal
@gmail.commailboxes and Google Workspace (formerly G Suite) accounts. Connect whichever one you want to send from. -
Do I still need to configure SMTP anywhere else in WordPress?
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No. Once activated and authenticated, it handles all outgoing email automatically. You do not need PHP mailer constants,
wp-config.phpchanges, or a second SMTP plugin — and you should not run another mailer plugin alongside it. -
Will it work with WooCommerce, Contact Form 7, WPForms, and other plugins?
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Yes. It hooks
pre_wp_mail, so every email triggered by WooCommerce (order confirmations, receipts, low-stock alerts), Contact Form 7, WPForms, Fluent Forms, Gravity Forms, MemberPress, LearnDash, or any other plugin callingwp_mail()goes out through your Gmail mailbox. -
Can I test my configuration before going live?
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Yes. The Test Email tool in the Configuration tab sends a real message and reports back what happened, including the specific error when the send fails.
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The button appears only after you have entered and saved both the Client ID and Client Secret. Paste the values from Google Cloud Console, click Save Settings, then authenticate. Full steps are in the configuration guide.
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I get a “Redirect URI mismatch” error from Google. How do I fix it?
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The Authorized Redirect URI shown in Settings > SMTP Connect for Gmail > Configuration must match the URI in your Google Cloud OAuth client character for character (including
https://). Copy it with the Copy button and paste it into Google Cloud Console. If a security plugin is blocking the callback, see the OAuth Callback URL Troubleshooting guide. -
The test email says it cannot connect to smtp.gmail.com.
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Your host is blocking outbound SMTP on port 587. Ask them to allow traffic to
smtp.gmail.comon that port. See Troubleshooting. -
How do I disconnect or revoke access from my Google account?
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Click the “Delete Access Key” button in the Configuration tab to remove the stored tokens from your site. You can also revoke access at any time from your Google Account under “Third-party apps & services”, which stops the site sending immediately. Full steps are in the Revoking Access documentation.
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What exactly is stored in my database?
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Your OAuth Client ID and Client Secret, the access token and its expiry, the refresh token, and the connected account’s email address — in a single
web357_smtp_connect_gmail_settingsoption. No Google account password is ever stored, and uninstalling the plugin deletes the option. -
Is this plugin affiliated with Google?
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No. Gmail and Google Workspace are trademarks of Google LLC. This is an independent third-party integration built by Web357 and is not endorsed by or affiliated with Google.
For more answers, see the FAQ and Guides & Troubleshooting.
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Contributors & Developers
“Web357 SMTP Connect for Gmail” is open source software. The following people have contributed to this plugin.
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Changelog
11-Sep-2026 : v1.0.0
- First stable release
