Microsoft Exchange 365 Mailer (ok_exchange365_mailer)

A TYPO3 extension for sending emails via Microsoft Exchange 365 using the MS Graph API instead of SMTP. Uses OAuth 2.0 client credentials flow for secure, token-based authentication.

Features

• Send emails through Microsoft Graph API — no SMTP required
• OAuth 2.0 client credentials flow for server-to-server authentication
• Supports both backend (environment variables / TYPO3 settings) and frontend (TypoScript) configuration
• Compatible with Powermail, TYPO3 Form Framework, and other form extensions
• Optional saving of sent emails to the sender's "Sent Items" folder
• Automatic credential blinding in TYPO3's configuration module
• Works with shared mailboxes and Application Access Policies

Requirements

• TYPO3: 12.4 LTS, 13.4 LTS, or 14.x
• PHP: 8.3+
• Dependencies:
  • microsoft/microsoft-graph ^2
  • oliverkroener/ok-typo3-helper ^3

Installation

Install via Composer (recommended):

composer require oliverkroener/ok-exchange365-mailer

Local path repository

If using a local path (e.g., in a monorepo), add the repository to your root composer.json:

{
    "repositories": [
        {
            "type": "path",
            "url": "packages/ok_exchange365_mailer"
        }
    ]
}

Then install:

composer require oliverkroener/ok-exchange365-mailer:@dev

Configuration

1. Register an Azure App

Register an application in Microsoft Entra ID (formerly Azure AD) with Mail.Send and User.ReadBasic.All application permissions. Grant admin consent. See the full Azure setup guide.

2. Configure TYPO3

Set the mail transport to Exchange365Transport and provide your Azure credentials.

Via environment variables (.env):

Variable	Description
TYPO3_CONF_VARS__MAIL__transport	OliverKroener\OkExchange365\Mail\Transport\Exchange365Transport
TYPO3_CONF_VARS__MAIL__transport_exchange365_tenantId	Microsoft Entra ID Tenant ID
TYPO3_CONF_VARS__MAIL__transport_exchange365_clientId	Azure Application (Client) ID
TYPO3_CONF_VARS__MAIL__transport_exchange365_clientSecret	Azure Application Secret Value
TYPO3_CONF_VARS__MAIL__transport_exchange365_fromEmail	Sender email address (must exist in Exchange 365)
TYPO3_CONF_VARS__MAIL__transport_exchange365_saveToSentItems	1 to save to Sent Items, 0 to skip (default: 0)

Via TypoScript (for frontend forms):

plugin.tx_okexchange365mailer.settings.exchange365 {
    tenantId = your-tenant-id
    clientId = your-client-id
    clientSecret = your-client-secret
    fromEmail = service@your-domain.com
    saveToSentItems = 1
}

Sender Display Name

The Graph API uses the Display name configured on the mailbox in Exchange Online. TYPO3's defaultMailFromName has no effect. Configure the display name in the Microsoft 365 Admin Center or Exchange Admin Center.

Architecture

Component	Description
Exchange365Transport	Custom Symfony mailer transport; handles OAuth2 auth and sends via Graph API
ModifyBlindedConfigurationOptionsEventListener	PSR-14 event listener; blinds credentials in TYPO3 configuration module
MSGraphMailApiService (from ok-typo3-helper)	Converts Symfony email messages to Microsoft Graph format

Classes/
├── Mail/Transport/
│   └── Exchange365Transport.php
└── Lowlevel/EventListener/
    └── ModifyBlindedConfigurationOptionsEventListener.php
Configuration/
├── Services.yaml
├── TCA/Overrides/sys_template.php
└── TypoScript/
    ├── constants.typoscript
    └── setup.typoscript

License

GPL-2.0-or-later

Author — Oliver Kroener

Automated. Scaled. Done.

Web3 · Cloud · Automation

Technology is only valuable when it solves a real problem. For over 30 years I've been translating between business and tech — so your investment in digitalisation doesn't stall at proof-of-concept but delivers measurable results.

• Website: oliver-kroener.de
• Web3: web3.oliver-kroener.de
• Email: ok@oliver-kroener.de
• Web3 Email: oliverkroener@ethermail.io