Unable to migrate storage account from LRS to ZRS - ZrsNotSupportedForAccountWithBootDiagnosticEnabled error even though no VMs are using it

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@Ankit Thakkar I hope you are doing,

I hope you are doing well.

The error is expected if Azure still detects the storage account as being associated with Boot Diagnostics. Disabling Boot Diagnostics on the VMs is not necessarily enough; the storage account itself must no longer have that dependency when you submit the ZRS conversion. Microsoft explicitly states that LRS → ZRS conversions are blocked while Boot Diagnostics is enabled for the account. ([Microsoft Learn](https://learn.microsoft.com/en-us/azure/storage/common/redundancy-migration?utm_source=chatgpt.com"Change how a storage account is replicated - Azure Storage | Microsoft Learn"))

I would check the following before retrying:

1. Confirm there are no VMs still using the storage account for Boot Diagnostics.
2. Check for older/deallocated VMs, because they can be easy to overlook.
3. Verify the storage account is not referenced by any VM's bootDiagnostics.storageUri.
4. Wait a little after disabling Boot Diagnostics and then retry the conversion.
5. Confirm the account is a supported StorageV2 account and that ZRS is supported in East US.

You can also check the VM configuration with:

az vm list \

  --query "[].{VM:name,RG:resourceGroup,BootDiag:diagnosticsProfile.boot.storageUri}" \

  -o table

If no VM references the storage account and the same error continues, I would not recommend deleting or recreating the storage account just to clear the flag. There isn't a documented customer-facing command to manually clear an internal Boot Diagnostics association.

Also, the "contains no data" message from the migration assessment is a separate issue from the Boot Diagnostics validation. I would not use that message as evidence that the containers are actually empty. Microsoft's current documentation specifically confirms that Boot Diagnostics conflicts with ZRS and that the account must have Boot Diagnostics disabled before submitting the conversion. ([Microsoft Learn](https://learn.microsoft.com/en-us/azure/storage/common/redundancy-migration?utm_source=chatgpt.com"Change how a storage account is replicated - Azure Storage | Microsoft Learn"))

Microsoft documentation:

·       Change how a storage account is replicated https://learn.microsoft.com/en-us/azure/storage/common/redundancy-migration

·       Storage redundancy change FAQs https://learn.microsoft.com/en-us/azure/storage/common/storage-redundancy-change-faq

·       Azure Storage redundancy https://learn.microsoft.com/en-us/azure/storage/common/storage-redundancy

If you have already verified that no VM in the subscription references this account for Boot Diagnostics and the error persists after some time, I would then treat this as an Azure-side stale association and investigate it further rather than repeatedly retrying the migration.

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I’m not sure of the exact reason, but I deleted the container whose name started with bootdiagnostics, and after that I was able to change the storage account from LRS to ZRS successfully.