Microsoft 365 email setup in Regal Send

Updated September 24, 2026

Microsoft 365 email setup in Regal Send connects WordPress to one Microsoft mailbox through Microsoft Graph. The guided wizard explains each Microsoft Entra task, shows where to find the required IDs and provides the exact redirect URI for the site.

Before starting Microsoft 365 email setup#

• You need permission to create or manage an app registration in Microsoft Entra.
• You need access to the Microsoft mailbox that will send WordPress email.
• The WordPress site must use HTTPS.
• If the From Email differs from the connected mailbox, the connected account needs Exchange Send As permission for that address.

Open the guided wizard#

1. In WordPress, open Regal Send and select Microsoft 365 / Outlook.
2. Select Open guided Microsoft setup.
3. Keep the wizard open in one browser tab and Microsoft Entra in another.

Create the Microsoft Entra app registration#

1. Use the wizard link to open Microsoft Entra App registrations.
2. Select New registration, enter a recognisable name and choose the required supported account type.
3. Select Register.
4. On the app Overview page, find the Application (client) ID and Directory (tenant) ID in the Essentials panel. Copy both values.

Microsoft also provides official app-registration instructions.

Add the Web redirect URI#

1. In the app, open Authentication.
2. Select Add a platform and choose Web.
3. Copy the redirect URI displayed by the Regal Send wizard and paste it into Microsoft Entra exactly as shown.
4. Save the change.

Do not alter the protocol, hostname, port or path. See Microsoft’s redirect URI instructions if the platform option is unavailable.

Add the required delegated permissions#

1. Open API permissions and select Add a permission.
2. Choose Microsoft Graph, then Delegated permissions.
3. Add Mail.Send and User.Read.
4. Grant administrator consent only when required by the organisation’s Microsoft policy.

Do not add application Mail.Send. Regal Send sends as the signed-in mailbox and does not request application-wide mailbox access.

Create the client secret#

1. Open Certificates & secrets, select Client secrets, then select New client secret.
2. Create the secret with an expiry period appropriate for the organisation.
3. Immediately copy the secret Value. Do not copy the Secret ID. Microsoft displays the Value only once.

See Microsoft’s credential instructions for more detail.

Save and connect Regal Send#

1. Return to the Regal Send wizard.
2. Paste the Application (client) ID.
3. Choose the supported account type that matches the app registration.
4. For a single-tenant app, paste the Directory (tenant) ID from the app Overview page.
5. Paste the client secret Value.
6. Enter the From Email and From Name.
7. Select Save and connect Microsoft, sign in as the sending mailbox and approve the requested delegated access.
8. When the status shows Connected, send a test email.

Common setup problems#

Microsoft reports a redirect URI mismatch#

Confirm that the Web redirect URI in Microsoft Entra exactly matches the URI displayed by Regal Send. Check the protocol, hostname, port and full path.

The client secret is rejected#

Create a new client secret and copy its Value immediately. A Secret ID is not a usable credential. A blank Regal Send secret field keeps an existing encrypted value unchanged.

The tenant cannot be found#

Open the app registration and select Overview. Copy the Directory (tenant) ID from the Essentials panel. Use it only when the wizard is set to one specific tenant.

The test email is rejected for the From address#

Use the connected mailbox as the From Email, or grant that mailbox Exchange Send As permission for the configured From address. Reconnect Microsoft after changing the account or permissions.

What a successful test means#

A successful test means Microsoft accepted the message for delivery. It does not prove inbox placement. Review the recipient mailbox, Regal Send Email Logs and the delivery health checks when further diagnosis is needed.