Configure Google Gmail email in Regal Send

Updated September 20, 2026

Configure Google Gmail email in Regal Send when you want WordPress to send through an authorised Google Workspace or Gmail mailbox using the Gmail API. Regal Send requests only the Gmail send permission and offline access, stores credentials and tokens in encrypted form, and sends the final prepared message as raw MIME.

Before you configure Google Gmail email#

You need administrator access to WordPress and permission to create or manage a project in Google Cloud. The WordPress site must use HTTPS, and its path-based WordPress REST API callback must be reachable from Google. The local Trial and Premium test sites use HTTP, so their Connect Google button is intentionally unavailable.

• Choose the Google account that will authorise sending.
• Confirm that the intended From Email is that mailbox or a sender alias configured for it.
• Have access to Google Cloud Console.
• Ensure the public WordPress site uses HTTPS and does not block its REST API.

Enable the Gmail API#

1. Open Google Cloud Console and create or select the project for this WordPress site.
2. Open APIs and Services, then Library.
3. Find Gmail API and enable it for the project.
4. Open the OAuth consent configuration and complete the required app information for your organisation or users.
5. Add the Gmail API scope https://www.googleapis.com/auth/gmail.send. Regal Send does not request read, delete or mailbox-management access.

Google may require additional testing-user or verification steps depending on the audience and publishing status of your OAuth app. Follow the current Google OAuth policies for the account type and intended users.

Create the Google OAuth web application#

1. In Google Cloud Console, open APIs and Services, then Credentials.
2. Create an OAuth client ID and select Web application.
3. In WordPress, open Regal Send, choose Google / Gmail, and copy the Authorised redirect URI shown in the provider panel.
4. Add that exact HTTPS address to the OAuth client’s authorised redirect URIs. Do not add, remove or alter a path segment, query string, port or trailing slash.
5. Copy the generated Client ID and client secret.

Google’s OAuth 2.0 web server guide explains the web application flow and redirect URI requirements.

Save and connect Google in Regal Send#

1. In Regal Send, choose Google / Gmail.
2. Paste the OAuth Client ID and client secret into the Google provider panel.
3. Set the From Email and From Name needed by the site. Enable Force From Email only when every WordPress email should use that address.
4. Select Save settings.
5. Select Connect Google.
6. Sign in with the sending Google account and grant the requested permission.
7. Return to Regal Send and confirm that the provider state is Connected.

The client secret, access token and refresh token are encrypted and are not rendered back into the settings page. The OAuth state is single-use and protected with PKCE. Access tokens are refreshed automatically when needed.

Connection states and what they mean#

• Not configured: the Client ID, client secret or HTTPS callback requirement is missing.
• Awaiting authorisation: a connection was started but Google sign-in or consent has not completed.
• Connected: Regal Send has a refresh token and can request an access token for Gmail sending.
• Authentication problem: the grant was revoked, expired or could not be refreshed. Use Reconnect Google.

From addresses and aliases#

The Gmail API sends as the connected mailbox. If WordPress uses a different From Email, that address must be an authorised send-as alias for the connected account. Gmail can reject the request when the From header does not match the mailbox or an allowed alias. Correct the sender in Google, change the WordPress From Email, or connect the appropriate mailbox.

Troubleshoot Google Gmail email sending#

The Connect Google button is unavailable#

Check that the site URL and callback use HTTPS, that the WordPress REST API is available at the path shown in Regal Send, and that a valid Web application Client ID and secret have been saved.

Google reports a redirect URI mismatch#

Copy the callback from Regal Send again and compare it character for character with the authorised redirect URI in Google Cloud. Use the exact scheme, host, port and path.

Google consent was denied#

No connection is saved. Start Connect Google again and approve the Gmail send permission using the intended sending account.

The connection needs authorisation again#

The Google grant may have been revoked or become invalid. Select Reconnect Google and complete consent again. If the app credentials changed, save the replacement Client ID or secret before reconnecting.

Gmail rejects the message#

Confirm that Gmail API is enabled, the connected account still has the Gmail send permission, and the From Email is the mailbox or a configured sender alias. Check the Email Logs entry for the safe error category and HTTP status. Regal Send does not expose Google’s raw provider message when it might contain sensitive details.

Disconnect or replace the Google connection#

Select Disconnect to delete saved Google access and refresh tokens while keeping the Client ID and client secret. Use the removal checkbox and save settings if you also need to remove the saved client secret. Changing the Client ID clears the existing connection, so reconnect after saving the new credentials.