Can't create an event grid for incoming calls

Question

Hi there,

I'm trying to set up a new phone number in D365 Copilot Service Admin Center. I purchased the number and I need to set up the event grid. I'm following the instructions below and getting the following error:

Deploying Event Subscription: IncomingCallsWebhook

Deployment has failed with the following error: {"code":"WebhookAadAppAccessCheckCategory","message":"Access check failed for Webhook AAD App with error 'AAD Application 'XXXXbfda-XXXX-4d07-XXXX-7ec83XXXXXXX' not found.'. For troubleshooting, visit https://aka.ms/essecurewebhook. Activity id:804ecf0b-a6fc-413f-ac26-0cfca44f5454, timestamp: 11/11/2025 12:51:27 AM (UTC)."}

Microsoft Documentation: Get application and tenant IDs from the Power Apps portal

Any ideas on why this happening?

Thanks so much!

edited PII information

Answer 1

It seems that you're encountering an issue with the Event Subscription for incoming calls due to an access check failure related to the Azure Active Directory (AAD) application. The error message indicates that the AAD Application with the specified ID was not found. Here are a few steps you can take to troubleshoot this issue:

1. Verify AAD Application: Ensure that the AAD Application ID (c439bfda-b873-4d07-a7ef-7ec839b0c70e) exists in your Azure Active Directory. You can do this by checking the app registrations in the Azure portal.
2. Check Permissions: Make sure that the application has the necessary permissions to access the resources it needs. You may need to assign roles or permissions to the application in the Azure portal.
3. Correct Tenant ID: Ensure that you are using the correct Microsoft Entra Tenant ID and Application ID. These values should match those defined in your organization.
4. Event Grid Configuration: Follow the steps in the documentation to ensure that your Event Grid is properly configured for incoming calls. You can refer to the section on setting up the incoming calls webhook for guidance.
5. Retry After Changes: After making any necessary changes, wait a few minutes and then try to create the event subscription again, as it can take some time for changes to propagate.

If the problem persists, consider checking the logs for more detailed error messages or reaching out to Microsoft support for assistance.

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References:

• Get Event Grid app and tenant IDs from the Power Apps portal
• Set up the incoming calls webhook

Answer 2

HI @Aisha Patel

When setting up secure webhooks for Dynamics 365 voice channel features like incoming calls, SMS, or call recording, Azure Event Grid uses an AAD app registration for authentication. If you see the error "AAD Application 'c439bfda-b873-4d07-a7ef-7ec839b0c70e' not found," it's typically an access validation failure during deployment. This doesn't mean the app is deleted, but rather that your account can't verify it. Possible reasons include:

• Using the wrong tenant or app ID.
• The app wasn't provisioned correctly in Power Apps (rare, since Dataverse usually handles this automatically).
• You aren't listed as an owner of the app registration.

kindly proceed with the following steps:

Check App Registration and Retrieve IDs:

• Navigate to Power Apps maker portal and select your environment. Go to Dataverse > Tables > All.
• Search for "Communication Provider Setting Entry," open it, and note the EventGridAppID (should be c439bfda-b873-4d07-a7ef-7ec839b0c70e) and EventGridAppTenantID from the Values column.
• Next, go to Azure Portal, then Microsoft Entra ID > App registrations, and search using the ID. If not found (rare), follow the Power Apps steps below to reconfigure. Create/Reconfigure the App (Only if Missing):
• Follow Get IDs from Power Apps—it provisions the app automatically for your Azure Communication Services resource.
• Use these IDs in Event Grid (no manual creation needed otherwise).

Assign Permissions:

• In the app, go to Owners, select + Add owners, add your account, and click Save.
• To ensure secure delivery, make sure your account has the AzureEventGridSecureWebhookSubscriber role. You can assign this role using PowerShell if necessary. Refer to Troubleshoot Secure Webhooks for the relevant scripts.

Retry Deployment:

• Go to the Azure Portal, select your ACS resource, then navigate to Events > + Event Subscription.
• Under Basics, set the name as IncomingCallsWebhook, filter for "Incoming Call", and use the webhook from Copilot Service (Channels > Phone Numbers > Advanced > Manage ACS).
• In Additional Features, enable Entra authentication, enter the Tenant and App IDs, and click Create.Allow 5-15 minutes for synchronization, then test in the Copilot Service Admin Center.

If the issue persists, could you please confirm the following information:

1. Are you using the same account across Power Apps, Copilot Service, and Azure?
2. Does the EventGridAppID in Dataverse correspond to the error ID?
3. Is this a trial tenant or a production tenant?

reference:

https://learn.microsoft.com/en-us/dynamics365/customer-service/administer/voice-channel-configure-services#get-event-grid-app-and-tenant-ids-from-the-power-apps-portal

https://learn.microsoft.com/en-us/azure/event-grid/secure-webhook-delivery

Kindly let us know if the above helps or you need further assistance on this issue.