The objects available within our connector are accessible from the "cdata.exchange" module. To use the module's objects directly:

1. Import the module as follows:
   

   import cdata.exchange as mod

2. To establish a connection string, call the connect() method from the connector object using an appropriate connection string, such as:
   

   mod.connect("User='[email protected]';Password='myPassword';Server='https://outlook.office365.com/EWS/Exchange.asmx';Platform='Exchange_Online';Schema='EWS';")

Connecting to Microsoft Exchange

There are two schemas available for connecting to Exchange:

• Microsoft Graph
• Exchange Web Services (EWS) (deprecated)
  Note: Microsoft recommends that Exchange Online users switch to Microsoft Graph.

For a look at the data model for each of these schemas, see Data Model

To switch between Microsoft Graph and EWS, set Schema to either MSGraph or EWS (deprecated).

Exchange Online users who still want to use EWS should set Schema to EWS and the Platform to Exchange_Online.

Authenticating to Microsoft Exchange OnPremises

Microsoft Exchange OnPremises supports Basic (default), Digest, Negotiate, or NTLM authentication.

Basic (default)

Microsoft Exchange OnPremises defaults sets Basic as the default authentication. To support Basic authentication, set these properties:

• AuthScheme: Basic.
• User: The user's login ID.
• Password: The user's login password.

Digest

To support HTTP Digest authentication in an On-Premises deployment, set these properties:

• AuthScheme: Digest.
• User: The user's login ID.
• Password: The user's login password.

Negotiate

Negotiate is used to direct the driver to negotiate an authentication mechanism with the server. The purpose of this authscheme is to facilitate Kerberos authentication in an On-Premises deployment. To support Kerberos authentication in an On-Premises deployment, set these properties:

• AuthScheme: Negotiate.
• User: The user's login ID.
• Password: The user's login password.

NTLM

To use Windows NT LAN Manager (NTLM) authentication in an On-Premises deployment, set these parameters:

• AuthScheme: NTLM.
• User: The user's login Id.
• Password: The user's login password.

Authenticating to Microsoft Exchange Online

Microsoft Exchange Online supports several types of OAuth-based authentication.

If you are connecting to Exchange Online platform through EWS, set AuthScheme to AzureAD, AzureServicePrincipal, or AzureMSI.

If you connect to Exchange Online through Microsoft Graph, set Schema to MSGraph. When Schema is set to MSGraph, the Platform is ignored.

Entra ID (Azure AD)

Note: Microsoft has rebranded Azure AD as Entra ID. In topics that require the user to interact with the Entra ID Admin site, we use the same names Microsoft does. However, there are still CData connection properties whose names or values reference "Azure AD".

Microsoft Entra ID is a multi-tenant, cloud-based identity and access management platform. It supports OAuth-based authentication flows that enable the driver to access Microsoft Exchange endpoints securely.

Authentication to Entra ID via a web application always requires that you first create and register a custom OAuth application. This enables your application to define its own redirect URI, manage credential scope, and comply with organization-specific security policies.

For full instructions on how to create and register a custom OAuth application, see Creating an Entra ID (Azure AD) Application.

After setting AuthScheme to AzureAD, the steps to authenticate vary, depending on the environment. For details on how to connect from desktop applications, web-based workflows, or headless systems, see the following sections.

Desktop Applications

You can authenticate from a desktop application using either the driver's embedded OAuth application or a custom OAuth application registered in Microsoft Entra ID.

Option 1: Use the Embedded OAuth Application

This is a pre-registered application, included with the driver. It simplifies setup and eliminates the need to register your own credentials and is ideal for development environments, single-user tools, or any setup where quick and easy authentication is preferred.

Set the following connection properties:

• AuthScheme: AzureAD
• InitiateOAuth:
  • GETANDREFRESH – Use for the initial login. Launches the login page and saves tokens.
  • REFRESH – Use this setting when you have already obtained valid access and refresh tokens. Reuses stored tokens without prompting the user again.

When you connect, the driver opens the Microsoft Entra sign-in page in your default browser. After signing in and granting access, the driver retrieves the access and refresh tokens and saves them to the path specified by OAuthSettingsLocation.

Option 2: Use a Custom OAuth Application

If your organization requires more control, such as managing security policies, redirect URIs, or application branding, you can instead register a custom OAuth application in Microsoft Entra ID and provide its values during connection.

During registration, record the following values:

• OAuthClientId: The client Id that was generated when you registered your custom OAuth application.
• OAuthClientSecret: The client secret that was that was generated when you registered your custom OAuth application.
• CallbackURL: A redirect URI you defined during application registration.

For full instructions on how to register a custom OAuth application and configure redirect URIs, see Creating an Entra ID (Azure AD) Application.

Set the following connection properties:

• AuthScheme: AzureAD
• InitiateOAuth:
  • GETANDREFRESH – Use for the initial login. Launches the login page and saves tokens.
  • REFRESH – Use this setting when you have already obtained valid access and refresh tokens. Reuses stored tokens without prompting the user again.
• OAuthClientId: The client Id that was generated when you registered your custom OAuth application.
• OAuthClientSecret: The client secret that was generated when you registered your custom OAuth application.
• CallbackURL: A redirect URI you defined during application registration.

After authentication, tokens are saved to OAuthSettingsLocation. These values persist across sessions and are used to automatically refresh the access token when it expires, so you don't need to log in again on future connections.

Web Applications

To authenticate from a web application, you must register a custom OAuth application in Microsoft Entra ID (formerly Azure Active Directory). Embedded OAuth apps are not supported in this context because web-based flows require a registered redirect URI and centralized credential management.

This approach is designed for hosted, multi-user environments where access must be delegated through a secure, standards-compliant OAuth workflow. It gives your organization control over the OAuth client, redirect URI, branding, and permissions scope.

Before you begin: Register a custom OAuth application in the Azure portal. During registration, collect the following values:

• OAuthClientId: The client Id that was generated when you registered your custom OAuth application.
• OAuthClientSecret: The client secret that was generated when you registered your custom OAuth application.
• CallbackURL: A redirect URI you defined during application registration.

For full instructions on how to register a custom OAuth application and configure redirect URIs, see Creating an Entra ID (Azure AD) Application.

To authenticate using AzureAD in a web application, configure the following connection properties:

• AuthScheme: AzureAD
• InitiateOAuth: OFF – Disables automatic login prompts.
• OAuthClientId: The client Id that was generated when you registered your custom OAuth application.
• OAuthClientSecret: The client secret that was generated when you registered your custom OAuth application.
• CallbackURL: A redirect URI you defined during application registration.

Because web applications typically manage OAuth flows manually on the server-side, InitiateOAuth must be set to OFF. This allows you to explicitly control when and how tokens are retrieved and exchanged using stored procedures.

After configuring these properties, follow the steps below to obtain and exchange OAuth tokens:

1. Call the GetOAuthAuthorizationURL stored procedure:
   • CallbackURL: Set to your registered redirect URI
2. Open the returned URL in a browser. Sign in with a Microsoft Entra ID account and grant access.
3. After signing in, you are redirected to your CallbackURL with a code parameter in the query string.
4. Extract the code and pass it to the GetOAuthAccessToken stored procedure:
   • AuthMode: WEB
   • Verifier: The authorization code from the CallbackURL
5. The procedure returns:
   • OAuthAccessToken: Used for authentication.
   • OAuthRefreshToken: Used to refresh the access token.
   • ExpiresIn: The lifetime of the access token in seconds.

To enable automatic token refresh, configure the following connection properties:

• InitiateOAuth: REFRESH
• OAuthRefreshToken: Your previously obtained refresh token

When InitiateOAuth is set to REFRESH, the driver uses the provided refresh token to request a new access token automatically.

After a successful connection, the driver saves the updated access and refresh tokens to the file specified by OAuthSettingsLocation.

You only need to repeat the full OAuth authorization flow if the refresh token expires, is revoked, or becomes invalid.

For more background on OAuth flows in Microsoft Entra ID, see Microsoft Entra Authentication Overview.

Headless Machines

Headless environments like CI/CD pipelines, background services, or server-based integrations do not have an interactive browser. To authenticate using AzureAD, you must complete the OAuth flow on a separate device with a browser and transfer the authentication result to the headless system.

Setup options:

• Obtain and exchange a verifier code
  • Use another device to sign in and retrieve a verifier code, which the headless system uses to request tokens.
• Transfer an OAuth settings file
  • Authenticate on another device, then copy the stored token file to the headless environment.

Using a Verifier Code

1. On a device with a browser:
   • If using a custom OAuth app, set the following properties:
     • InitiateOAuth: OFF
     • OAuthClientId: The client Id that was generated when you registered your custom OAuth application.
     • OAuthClientSecret: The client secret that was generated when you registered your custom OAuth application.
   • Call the GetOAuthAuthorizationURL stored procedure to generate a sign-in URL.
   • Open the returned URL in a browser. Sign in and grant grant permissions to the driver. You are redirected to the callback URL, which contains the verifier code.
   • After signing in, save the value of the code parameter from the redirect URL. You will use this later to set the OAuthVerifier connection property.
2. On the headless machine:
   • Set the following properties:
     • AuthScheme: AzureAD
     • InitiateOAuth: REFRESH
     • OAuthVerifier: The verifier code you saved.
     • OAuthSettingsLocation: The path of the file that holds the OAuth token values.
     • For custom applications:
       • OAuthClientId: The client Id that was generated when you registered your custom OAuth application.
       • OAuthClientSecret: The client secret that was generated when you registered your custom OAuth application.
   • After tokens are saved, reuse them by setting:
     • InitiateOAuth: REFRESH
     • OAuthSettingsLocation: Make sure this location grants read and write permissions to the driver to enable the automatic refreshing of the access token.
     • For custom applications:
       • OAuthClientId: The client Id that was generated when you registered your custom OAuth application.
       • OAuthClientSecret: The client secret that was generated when you registered your custom OAuth application.

Transferring OAuth Settings

1. On a device with a browser:
   • Connect using the instructions in the Desktop Applications section.
   • After connecting, tokens are saved to the file path in OAuthSettingsLocation. The default filename is OAuthSettings.txt.

2. On the headless machine:
   • Copy the OAuth settings file to the machine.
   • Set the following properties:
     • AuthScheme: AzureAD
     • InitiateOAuth: REFRESH
     • OAuthSettingsLocation: Make sure this location grants read and write permissions to the driver to enable the automatic refreshing of the access token.
     • For custom applications:
       • OAuthClientId: The client Id that was generated when you registered your custom OAuth application.
       • OAuthClientSecret: The client secret that was generated when you registered your custom OAuth application.

After setup, the driver uses the stored tokens to refresh the access token automatically, no browser or manual login is required.

Azure Service Principal

Note: Microsoft has rebranded Azure AD as Entra ID. In topics that require the user to interact with the Entra ID Admin site, we use the same names Microsoft does. However, there are still CData connection properties whose names or values reference "Azure AD".

Azure Service Principal is role-based application-based authentication. This means that authentication is done per application, rather than per user. All tasks taken on by the application are executed without a default user context, but based on the assigned roles. The application access to the resources is controlled through the assigned roles' permissions.

For information about how to set up Azure Service Principal authentication, see Creating a Service Principal App in Entra ID (Azure AD).

Managed Service Identity (MSI)

If you are running Microsoft Exchange on an Azure VM and want to automatically obtain Managed Service Identity (MSI) credentials to connect, set AuthScheme to AzureMSI.

User-Managed Identities

To obtain a token for a managed identity, use the OAuthClientId property to specify the managed identity's client_id.

If your VM has multiple user-assigned managed identities, you must also specify OAuthClientId.