Configure Microsoft 365 Exchange Online as External SMTP Email Provider
Before you start
You must have a Microsoft 365 account with an active subscription.
Ensure your Microsoft 365 subscription is licensed to send emails through Exchange Online.
You need at a minimum a paid subscription to Microsoft Business Basic plan to use the Microsoft Graph API for Exchange Online.
Emails will be sent from Auth0 to your SMTP provider. Your ports should be open and allow inbound connections from specific Auth0 IP addresses. To learn more, read Auth0 IP Addresses for Allow Lists.
Update the list of IPs in Dashboard > Branding > Email Provider.
Auth0 allows you to configure your own SMTP email provider so you can manage, monitor, and troubleshoot your email communications.
Auth0's built-in email infrastructure should be used for testing emails only.
Configure Microsoft 365
Log in to Microsoft Azure account with your Microsoft 365 account.
Register a Azure Active Directory Application resource if you currently do not have one.
Navigate to your Active Directory Application resource. Select Services > App registrations, and then select the application you will be using to send emails.
Configure the required application permissions by navigating to Manage > API permissions.
Add the
Mail.Sendpermission by selecting Add a permission > Microsoft Graph > Application permissions selector.Before you configure Application permissions, you will need administrative consent.
Retrieve required provider configurations:
Navigate to the Application Overview to retrieve your application Client ID and Tenant ID.
Navigate to Manage > Certificates & secrets and collect the Value to create an application secret.
Retrieve the organization User Email that will send the emails through the application by Search > Users. Select Services > Users, select your authorized user, and then collect their User Email from their properties.
Navigate to Auth0 Dashboard > Branding > Email Provider.
Activate the Use my own email provider toggle.
Click the Microsoft 365 logo.
Provide the From email address. Then, enter the Tenant ID, Client ID, and Client Secret from step 6, and then click Save.
Send a test email
Send a test email using the Send Test Email button. If you have configured everything correctly, you will receive a confirmation email.
If you do not receive an email after a few minutes, please check your Auth0 logs for error codes. The Microsoft Exchange Email Usage page will now display delivery insights for all emails that have been sent to your users.