I just ran into a frustrating error that seemed unexplainable to me. My goal was to replace an existing Azure Resource Group with a new one managed entirely with Terraform. Besides a few other errors, this SoftDeletedVaultDoesNotExist was incredibly confusing because no more Key Vaults were found in the Resource Group’s list of resources.

Error: creating Vault: (Name "my-fancy-key-vault" / Resource Group "The-Codeslinger"): 
keyvault.VaultsClient#CreateOrUpdate: Failure sending request: StatusCode=0 -- 
Original Error: Code="SoftDeletedVaultDoesNotExist" 
Message="A soft deleted vault with the given name does not exist. 
Ensure that the name for the vault that is being attempted to recover is in a recoverable state. 
For more information on soft delete please follow this link https://go.microsoft.com/fwlink/?linkid=2149745"

with module.base.azurerm_key_vault.keyvault,
on terraform\key_vault.tf line 9, in resource "azurerm_key_vault" "keyvault":
    9: resource "azurerm_key_vault" "keyvault" {

That is because it was soft-delete enabled. And it was the Key Vault from the other Resource Group that I previously cleared of all resources, not the new Resource Group.

Using the az CLI you can display it, though.

> az keyvault list-deleted

[
    {
        "id": "/subscriptions/<subscription-id>/providers/Microsoft.KeyVault/locations/westeurope/deletedVaults/my-fancy-key-vault",
        "name": "my-fancy-key-vault",
        "properties": {
            "deletionDate": "2021-08-02T09:39:29+00:00",
            "location": "westeurope",
            "purgeProtectionEnabled": null,
            "scheduledPurgeDate": "2021-10-31T09:39:29+00:00",
            "tags": {
                "customer": "The-Codeslinger",
                "source": "Terraform"
            },
            "vaultId": "/subscriptions/<subscription-id>/resourceGroups/My-Other-ResourceGroup/providers/Microsoft.KeyVault/vaults/my-fancy-key-vault"
        },
        "type": "Microsoft.KeyVault/deletedVaults"
    }
]

And finally delete it.

> az keyvault purge --name my-fancy-key-vault

After that, it is gone.

$ az keyvault list-deleted
[]

Another option seems to be the Azure Portal, but I discovered this only after removing it on the command line.