Effective October 1, 2022, Microsoft began disabling Basic authentication for Outlook, EWS, RPS, POP, IMAP, and EAS protocols in Exchange Online. This means that for TeleMessage import sources using Exchange will no longer work with simple username and password authentication, instead OAuth 2.0 authentication must be used.
Register application in Azure
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Step 3 - Go to Azure Active Directory. If it's not on the opening page, use the search or find it under All services.
Step 4 - Select App registrations on the left, and click on New registration.
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Step 8 - The two other values we need from the application is the application (client) id and the directory (tenant) id. Both can be copied from Overview:
Configure TeleMessage import source
On the Import source configuration page, select OAuth 2.0 for Authentication Mode, and set Application (Client) ID, Application (Client) Secret, Directory (Tenant) ID to their respective values from the registered Azure application above.
Register service principals in Exchange
This whole section is quoted from here: Authenticate an IMAP, POP or SMTP connection using OAuth
Once your Azure AD application is consented to by a tenant admin, the tenant admin must register your AAD application's service principal in Exchange via Exchange Online PowerShell. This is enabled by the New-ServicePrincipal cmdlet.
To use the New-ServicePrincipal cmdlet, install the ExchangeOnlineManagement and connect to your tenant as shown in the following snippet.
Install-Module -Name ExchangeOnlineManagement -allowprerelease
Import-module ExchangeOnlineManagement
Connect-ExchangeOnline -Organization <tenantId> |
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If you still get an error running the New-ServicePrincipal Cmdlet after you perform these steps, it is likely due to the fact that the user doesn't have enough permissions in Exchange online to perform the operation.
The following is an example of registering an Azure AD application's service principal in Exchange:
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The OBJECT_ID is the Object ID from the Overview page of the Enterprise Application node (Azure Portal) for the application registration. It is not the Object ID from the Overview of the App Registrations node. Using the incorrect Object ID will cause an authentication failure.
The tenant admin can find the service principal identifiers referenced above in your AAD application's enterprise application instance on the tenant. You can find the list of the enterprise application instances on the tenant in the Enterprise applications blade in the Azure Active Directory view in Azure Portal.
You can get your registered service principal's identifier using the Get-ServicePrincipal cmdlet.
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The tenant admin can now add the specific mailboxes in the tenant that will be allowed to be access by your application. This is done with the Add-MailboxPermission cmdlet.
The following is an example of how to give your application's service principal access to one mailbox:
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VFC can now access the allowed mailboxes via the POP or IMAP protocols using the OAuth 2.0 client credentials grant flow. For more information, see the instructions in Permissions and consent in the Microsoft identity platform.