Authorization for Organizations with Modern Authentication and Legacy Protocols or Basic Authentication

Since Microsoft deprecated basic authentication and legacy authentication protocols, Veeam Backup for Microsoft 365 version 8 does not support adding new Microsoft 365 organizations using modern authentication method with legacy protocols allowed. Adding Microsoft 365 organizations using basic authentication method is only available in Microsoft Entra China region through REST API and PowerShell.

To explore and restore backups using the Veeam Backup for Microsoft 365 REST API, clients from tenant Microsoft 365 organizations from Microsoft Entra China region or if they were added to previous installations of the product using modern authentication with these legacy authentication methods, must authenticate themselves.

Veeam Backup for Microsoft 365 REST API authorization process is based on the OAuth 2.0 Authorization Framework and involves obtaining an access token and refresh token:

• Access token is a string that represents authorization issued to the client. It must be used in all requests during the current REST API session.
• Refresh token is a string that represents authorization granted to the client. It is used to obtain a new access token if the current access token expires or becomes lost.

Along with this pair of tokens, the Veeam Backup for Microsoft 365 REST API server issues an antiforgery token. The antiforgery token is stored in your REST API client, for example — in web browser cookies. It protects an access and refresh tokens during a web browser REST API session.

By default, both an access token and antiforgery tokens are required for the Veeam Backup for Microsoft 365 REST API authorization process. The antiforgery token is also required to obtain a new access token using the refresh token.

You can disable usage of the antiforgery token in the Veeam Backup for Microsoft 365 REST API authorization process. To do this, set the true value for the disable_antiforgery_token parameter. For more information, see Request Authorization Tokens.

Veeam Backup for Microsoft 365 REST API authorization process involves the following procedures:

• Requesting Authorization
• Using Refresh Token
• Performing Logout

Requesting Authorization

To obtain a pair of tokens, a client sends the POST HTTPS request to the Veeam Backup for Microsoft 365 REST API token path. The request body must contain credentials for authenticating to the tenant Microsoft organization.

A successfully completed operation returns the 200 OK response code and an access and refresh tokens in the response body. The client inserts the access token in headers of further requests to Veeam Backup for Microsoft 365 REST API. The refresh token must be saved locally.

Using Refresh Token

To obtain a new pair of tokens in case the access token expires or becomes invalid, the client sends the POST HTTPS request with the refresh token in the request body to the Veeam Backup for Microsoft 365 REST API token path. A successfully completed operation returns the 200 OK response code and a new pair of tokens in the response body.

Performing Logout

The given access token expires in 60 minutes once issued.

You can logout manually. To do this, send the POST HTTPS request to the /token/logout endpoint. After you log out, access and refresh tokens are expired. A successfully completed operation returns the 204 No Content response code. For more information, see Log Out.

When the client finishes working with the Veeam Explorer for Microsoft Exchange, Veeam Explorer for Microsoft SharePoint, Veeam Explorer for Microsoft OneDrive for Business or Veeam Explorer for Microsoft Teams, they can stop the restore session manually. Otherwise, the session will be stopped automatically. For more information, see Stop Restore Session.

Example Requests and Responses

The following example illustrates how the client and server communicate using requests and responses.

1. To obtain access and refresh tokens, send the POST HTTPS request to the Veeam Backup for Microsoft 365 REST API token path. In the request body, enter the credentials for authenticating to the tenant Microsoft organization.

Wait for the response from the server. A successfully completed operation returns the response code 200 OK.

The response body contains access and refresh tokens. Copy both tokens, insert an access token in headers of further requests. A refresh token must be saved locally.

2. When an access token expires you can either obtain it again or renew using a refresh token. To renew the access token, send the POST HTTPS request to the Veeam Backup for Microsoft 365 REST API token path. In the request body, enter the refresh token.

Wait for the response from the server. A successfully completed operation returns response code 200 OK and a new pair of tokens in the response body.