[Bug]: Hardcoded Azure OpenAI API version prevents using latest models

[SchulzOli]

Describe the issue

The System Application Azure OpenAI integration uses a hardcoded API version 2024-06-01 that cannot be configured or overridden by developers. This prevents Business Central extensions from using:

• Latest GPT-4o models (require API version 2024-12-01-preview or later)
• o1-series reasoning models (o1-mini, o1-preview, o1)
• Azure AI Foundry endpoints (*.inference.ml.azure.com)
• New content filter policies and API features

Code Location: System Application 27.0, Codeunit 7767 "AOAI Authorization"

UrlFormatTxt: Label 'https://%1.openai.azure.com/openai/models?api-version=2024-06-01', Locked = true;

The codeunit is marked Access = Internal, the procedure is local, and the label is Locked = true, making it impossible to extend or override from AL code.

Critical Compatibility Gap (January 2026):
Models compatible with API version 2024-06-01 (gpt-35-turbo, gpt-4 turbo-2024-04-09) have been deprecated/retired as of September 2025. New models require API versions that BC doesn't support, creating a blocker for AI development.

Expected behavior

Business Central should support modern Azure OpenAI deployments through one of these approaches:

Option 1: Update API Version
Update the hardcoded API version to the latest stable version (2024-10-21 or newer) to support current model generations.

Option 2: Make API Version Configurable (Preferred)
Add a public method to allow developers to specify the API version:

procedure SetApiVersion(ApiVersion: Text)

This would provide backward compatibility while enabling access to latest features without waiting for platform updates.

Option 3: Support Multiple Endpoint Formats
Allow Azure AI Foundry and legacy endpoint formats in addition to the current .openai.azure.com restriction.

Steps to reproduce

1. Create Azure OpenAI Resource:

   • Navigate to Azure Portal
   • Create Azure OpenAI Service resource
   • Deploy model: gpt-4o (version 2024-11-20) or o1-mini
   • Note the endpoint URL and deployment name

2. Configure Business Central:

   • Create AL extension using System Application Azure OpenAI codeunits
   • Use SetAuthorization() with endpoint, deployment name, and API key
   • Set capability with SetCopilotCapability()

3. Attempt API Call:

   AOAIChatMessages.AddSystemMessage('Test');
   AOAIChatMessages.AddUserMessage('Hello');
   AzureOpenAI.GenerateChatCompletion(AOAIChatMessages, AOAIChatCompletionParams, AOAIOperationResponse);

4. Observe Result:

   • Status Code: 400
   • Error: "invalid content filter policy" or similar API version incompatibility error

5. Verification with Python SDK:

   # Same Azure resource, deployment, and API key with api_version="2024-12-01-preview"
   # Result: Works successfully

The issue is confirmed to be the hardcoded API version, not deployment configuration.

Additional context

Environment:

• Business Central: 27.0.38460.44704 (also affects earlier versions)
• System Application: 27.0.0.0
• Deployment: Both SaaS and On-Premises
• Azure OpenAI: All regions

Microsoft Documentation:

• Model Retirements: https://learn.microsoft.com/en-us/azure/ai-foundry/openai/concepts/model-retirements
• Latest stable API version: 2024-10-21
• Preview API version: 2024-12-01-preview
• v1 API (August 2025): No api-version required, uses /openai/v1/ path

Source Code Reference (Verified):

• Repository: microsoft/BCApps
• File: src/System Application/App/AI/src/Azure OpenAI/AOAIAuthorization.Codeunit.al
• Line 168: UrlFormatTxt: Label 'https://%1.openai.azure.com/openai/models?api-version=2024-06-01', Locked = true;
• Codeunit 7767 marked Access = Internal
• Procedure PerformAOAIAccountVerification is local

I will provide a fix for a bug

• I will provide a fix for a bug

[TianaMilicevic]

Is a hotfix planned for this issue? This is a show-stopper for us and blocks our AI features in Business Central. Any update on priority or timeline?

[SchulzOli]

same here

[sofiaagm-pereira]

Has anyone been able to find a solution to this? It seems that I have no issues connecting to a model in EU BC environments, but in others yes.

[darjoo]

I'm looking into this and will hotfix this issue.

From what I can tell, that check is being removed in v28.0.

[sofiaagm-pereira]

As a workaround to the "invalid content filter policy" error, a custom content filter policy needs to be created in Azure Foundry using the name of one of the possible enum values of the AOAI Policy enum and assign it to the deployed model. This fixed our connection issues.

[darjoo]

To add on to what @sofiaagm-pereira mentioned, there are 3 options for that mitigation.

1. Create your own policy and set the policy in AL code with SetCustomAOAIPolicy
2. Only set the policy in AL code with SetCustomAOAIPolicy with Microsoft.Default or Microsoft.DefaultV2
3. Only create a new policy and name that policy ConservativeWithXPIA. You do not need any AL code change for this.

[darjoo]

There are two issues and they're separate which we're hotfixing both.

1. Invalid content filter policy - Specifically for non-managed resources (bring your own Azure OpenAI)
2. API version - Specifically for managed resources (Using BC's resources)

[darjoo]

I'll close this for now. The hotfixes are beginning their rollout. If in the worst case, after 2 weeks you notice that you still run into any of these issues (On version 27.0 and up), do ping me here or in a new issue.

Thank you for bringing this to our attention!

[SchulzOli]

thanks a lot @darjoo