Registering Resource Providers in Azure: Fix 'Not Registered' Errors

What Resource Providers Are

A resource provider is a service in Azure that supplies a set of resource types. Every resource you create belongs to exactly one provider. The provider namespace appears in resource IDs and REST API URLs as the segment after /providers/:

/subscriptions/{id}/resourceGroups/{rg}/providers/Microsoft.Compute/virtualMachines/{name}
/subscriptions/{id}/resourceGroups/{rg}/providers/Microsoft.Storage/storageAccounts/{name}
/subscriptions/{id}/resourceGroups/{rg}/providers/Microsoft.KeyVault/vaults/{name}

Resource providers are maintained by Microsoft (for first-party Azure services) and by third-party publishers in the Azure Marketplace. For the services you use day-to-day, you are dealing with Microsoft’s built-in providers.

Understanding providers also helps when reading ARM templates, Bicep files, or Terraform configurations — the provider namespace is always part of the resource type definition. See Understanding Azure REST APIs for how provider namespaces appear in API URLs.

Why Registration Is Required

Azure does not automatically enable every provider on every subscription. Registration is a one-time acknowledgment that tells Azure “this subscription will use resources from this provider.” It also allows Azure to apply any terms of service or compliance checks associated with a service before you can create resources with it.

Some providers are registered by default on every new subscription. Others are not. When you try to create a resource from an unregistered provider, you get an error rather than a working resource.

The Exact Error You Will See

When you try to create a resource and the provider is not registered, Azure CLI returns an error similar to this:

(MissingSubscriptionRegistration) The subscription is not registered to use namespace 'Microsoft.ContainerService'.
See https://aka.ms/rps-not-found for how to register subscriptions.
Code: MissingSubscriptionRegistration
Message: The subscription is not registered to use namespace 'Microsoft.ContainerService'.
See https://aka.ms/rps-not-found for how to register subscriptions.

In the portal, you see a similar message in the deployment failure details. The key piece of information is the namespace in the error: Microsoft.ContainerService in this example. That tells you exactly which provider to register.

This error is not a permissions problem — it is a configuration problem, and it is easy to fix.

How to Register a Provider via CLI

To register a provider, run:

az provider register --namespace Microsoft.ContainerService

Replace Microsoft.ContainerService with the namespace from your error message. The command returns immediately but registration runs asynchronously. Check the status:

az provider show --namespace Microsoft.ContainerService --query "registrationState" --output tsv

The state progresses from NotRegistered to Registering to Registered. Once it shows Registered, retry the original operation that failed.

To list all providers and their current registration state for your subscription:

az provider list --output table

This returns a long list. To filter to just registered providers:

az provider list --query "[?registrationState=='Registered'].namespace" --output tsv

To filter to unregistered providers (the ones you might need to register if you plan to use those services):

az provider list --query "[?registrationState=='NotRegistered'].namespace" --output tsv

How to Register a Provider in the Portal

If you prefer the portal:

1. In the portal, search for “Subscriptions” in the top search bar and click on your subscription.
2. In the left sidebar of the subscription blade, click Resource providers.
3. You see a list of all providers with their status. Use the search box at the top to filter by name.
4. Click the provider you want to register.
5. Click the Register button at the top of the page.
6. Wait for the status to change to Registered. Refresh the page to see the updated status.

Automatic Registration

Azure can automatically register providers when you create resources through the portal or CLI, if you have the right permissions. This behavior is controlled by a subscription-level setting. By default on new subscriptions, auto-registration is enabled.

With auto-registration on, if you create a storage account and Microsoft.Storage is not yet registered, Azure registers it automatically before creating the account. The process is transparent and you may not even notice it.

However, auto-registration can be disabled by subscription administrators for governance reasons — for example, to prevent teams from accidentally enabling services that have not been approved or budgeted. In that case, you will see the MissingSubscriptionRegistration error and need to manually register the provider.

To check whether auto-registration is enabled on your subscription, look in the Resource providers blade in the portal for a setting about automatic registration, or ask your subscription administrator. Enterprise subscriptions managed under Azure Policy often have this disabled.

Most Commonly Needed Providers

The following table lists the providers most commonly required for typical cloud workloads, along with what resources each one covers. These are the ones you are most likely to need to register explicitly if auto-registration is off:

If you are setting up a subscription for a new team, registering all the providers you know you will use at the start saves the friction of hitting the error mid-deployment.

To register multiple providers at once in a script:

for provider in \
  Microsoft.Compute \
  Microsoft.Storage \
  Microsoft.Network \
  Microsoft.KeyVault \
  Microsoft.ContainerService \
  Microsoft.Insights \
  Microsoft.OperationalInsights; do
  az provider register --namespace $provider
done

This loop starts registration for all listed providers asynchronously. After a few minutes, verify they are all registered:

az provider show --namespace Microsoft.ContainerService --query registrationState --output tsv

Unregistering Providers

You can unregister a provider to prevent teams from using a particular service:

az provider unregister --namespace Microsoft.ContainerService

This does not delete existing resources — if you have AKS clusters already running, they continue to run. Unregistering prevents creating new resources of that type. In practice, unregistering is an uncommon operation. If you need to prevent resource creation, Azure Policy is a more robust approach because it can also prevent re-registration.