409 error when deleting a AI Foundry deployment

Hello @Dafydd Jones ,

Welcome to Microsoft Q&A .Thank you for reaching out to us.

Based on the behavior observed, the deployment delete operation is consistently returning HTTP 409 (Conflict) across both the current and legacy Azure AI Foundry portal experiences. A 409 response indicates that the service is unable to complete the delete request because the deployment is currently in a conflicting state rather than because the request itself is invalid.

The two most common causes for this behavior are:

• The deployment is still being referenced by another Azure AI Foundry asset or dependent resource.
• The deployment is still processing a previous operation and has not yet reached a terminal state.

Other possible causes include resource locks or a backend resource state that is preventing deletion from completing. Since the issue has persisted for several days and reproduces across multiple portal experiences, the issue is less likely to be portal-related and more likely associated with one of these underlying conditions.

Please check if the following steps help-

1. Verifying whether the deployment is referenced by other resources Dependencies are one of the most common causes of deployment deletion conflicts. Please review whether the deployment is currently being used by:
   • Agents
   • Prompt Flows
   • Evaluations
   • Batch Jobs
   • Connections
   • Project default model settings
   • Applications configured to consume the deployment
   If any dependency exists, remove or update the reference and retry the deletion.
2. Verifying the deployment provisioning state If a deployment is still processing another operation, the service may reject delete requests until the operation reaches a terminal state. The current deployment state can be verified with:

      az cognitiveservices account deployment show \
       --resource-group <resource-group> \
       --name <account-name> \
       --deployment-name <deployment-name>
   

   Please confirm whether the deployment status is:
   • Succeeded
   • Creating
   • Updating
   • Deleting
   • Failed
3. Retrieving the detailed backend error The Azure AI Foundry portal frequently displays the generic message -Request failed with status code 409 Running the operation through Azure CLI often exposes the underlying service error and provides more actionable diagnostic information:

      az cognitiveservices account deployment delete \
       --resource-group <resource-group> \
       --name <account-name> \
       --deployment-name <deployment-name> \
       --debug
   

   Please capture:
   • error.code
   • error.message
   • x-ms-request-id
   • x-ms-client-request-id (if available)
4. Reviewing the Azure Activity Log Please locate the failed delete operation within the Azure Activity Log and collect:
   • Correlation ID
   • Operation ID
   • Request ID
   • Status/SubStatus
   • UTC timestamp of the failure
   These details frequently help identify the specific conflict condition associated with the delete request.
5. Validating Resource Locks and Permissions Please verify whether any CanNotDelete or ReadOnly locks exist on:
   • The Azure AI resource
   • The Resource Group
   • The Subscription
   In addition, please confirm that the account performing the operation has an appropriate role assignment such as:
   • Owner
   • Contributor
   • Cognitive Services Contributor
6. Considering persistent backend resource state conditions If dependencies, active operations, locks, and permissions have been ruled out, and the deployment continues to return 409 Conflict through both the portal and CLI after several days, the issue may indicate a stale backend resource state or incomplete cleanup state that requires deeper investigation. The diagnostic information collected above will help identify whether this scenario applies.

The following references might be helpful , please check them out

• az cognitiveservices account deployment | Microsoft Learn
• Azure Activity Log event schema - Azure Monitor | Microsoft Learn
• Lock your Azure resources to protect your infrastructure - Azure Resource Manager | Microsoft Learn
• What is Azure role-based access control (Azure RBAC)? | Microsoft Learn

Please let us know if the response was helpful

Thank you

Hello @Dafydd Jones ,

For better assistance could you please provide the following information

1. The complete error details, including the full error code and message body
2. What is the current provisioning state of the deployment and what does the Azure Activity Log show for the failed delete operation?
3. What exactly are you trying to delete (deployment, project, or resource)
4. Which model, model version and region of deployment?
5. Is the deployment referenced by any endpoints, prompt flows, agents, connections, batch jobs, or other dependent resources?
6. Does deleting the deployment using Azure CLI or REST API also fail with a 409 error?
7. Were any recent operations performed on this deployment, such as creation, update, scaling, or model replacement?
8. Are there any Azure resource locks (Delete/Read-only) or RBAC restrictions that could prevent deletion?

Thank you

Hello @Dafydd Jones ,

Following up to see if you had any chance to review the response

Thank you