After the initial setup of Veeam Backup for Microsoft Azure I’ve had two different issues.

The backup jobs finished with following warning:

Crash-consistent snapshot of XYZ has been created. Cannot download VSS agent binaries from the storage account: The subscription is not registered to use namespace 'Microsoft.ServiceBus'. See https://aka.ms/rps-not-found for how to register subscriptions.

 

Also FLR restores failed:

Preparing worker for restore failed. Error: Cannot find any worker. Worker deployment failed, see logs for details

 

Both of these messages had the same root cause and especially the first one already points to the right direction, the “Microsoft.ServiceBus” Resource Provider wasn’t registered in Microsoft Azure.

The solution is really simple, just register this Resource Provider via the Azure Portal or use the Azure Powershell.

Register-AzResourceProvider -ProviderNamespace Microsoft.ServiceBus

I’m not sure if this Resource Provider should be registered by default, and if so, why it wasn’t in my case. But during my research I’ve found a topic in the forums (and also the Powershell cmdlet), so it seems that this occurs occasionally: https://forums.veeam.com/veeam-backup-for-azure-f59/worker-deployment-failed-t77209.html