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MS O365 Admin - Migrating From Basic to Modern Authentication for Cisco Voicemail

Why do I have to make this change?

Microsoft is retiring Basic Authentication for Exchange Online October 1, 2022. (article = In order to retrieve your voicemails via your phone this will need to be completed.

If you do not complete this task the following features will no longer function:

  • MWI light on the phone indicating new voicemail
  • Ability to check Voicemail from your phone or calling a pilot number.
  • Remote Notification for new voicemails

You will still get your voicemails sent to your email address.

Register your application

To use OAuth, an application must have an application ID issued by Azure Active Directory. In this tutorial, it is assumed that the application is a console application, so you need to register your application as a public client with Azure Active Directory. You can register an application in the Azure Active Directory admin center or by using Microsoft Graph.

  1. Open a browser and navigate to the Azure Active Directory admin center and login using a personal account (aka: Microsoft Account) or Work or School Account.

  2. Select Azure Active Directory in the left-hand navigation, then select App registrations under Manage.

  3. Select New registration. On the Register an application page, set the values as follows.

  4. Choose Register. On the next page, copy the values of the Application (client) ID and Directory (tenant) ID and save them, you will need them later.


Configure for app-only authentication

To use application permissions, follow these additional steps.

  1. Select Manifest in the left-hand navigation under Manage.

  2. Locate the requiredResourceAccess property in the manifest, and add the following inside the square brackets ([]):


        "resourceAppId": "00000002-0000-0ff1-ce00-000000000000",
        "resourceAccess": [
                "id": "dc890d15-9560-4a4c-9b7f-a736ec74ec40",
                "type": "Role"
  3. Select Save.

  4. Select API permissions under Manage. Confirm that the full_access_as_app permission is listed.

  5. Select Grant admin consent for org and accept the consent dialog.

  6. Select Certificates & Secrets in the left-hand navigation under Manage.

  7. Select New client secret, enter a short description and select Add.

  8. Copy the Value of the newly added client secret and save it, you will need it later.


The 3 items Calltower needs

  • appId
  • Client Secret Value
  • tenantId
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