NServiceBus UseTransport not working after upgrading to .NET 6

I’m using NserviceBus with the Azure Function project ( NServiceBus.AzureFunctions.InProcess.ServiceBus). Application is using azure service bus as the transport and it is configured in function startup by using the below code

var transport = configuration.AdvancedConfiguration.UseTransport();
Everything was working fine in .NET Core 3.1 and Azure function version 3.0. Recently I upgrade the project to .NET 6 and Function version to 4.0. After the upgrade, functionEndpoint.Process is throwing a null reference exception.

If the UseTransport code is commented out in function startup, no exception is thrown and the messages are getting processed successfully. But I need to have the UseTransport in the startup configuration for the NServiceBus to set up the transport topology automatically. Please help me to resolve this issue.


There are known issues with host v4 and we’re working on a fix

that said your issue seems to be different. Can you share the full stack trace of the exception?



There are additional details in https://github.com/Particular/NServiceBus.AzureFunctions.InProcess.ServiceBus/issues/376