NServicebus : {WARN} failed raising transport message with ID =

Here's the scenario. I am on NServiceBus 3开发者_如何学Go.0.0.1504 (core dll version). I get above warning message when there's an exception on one of the handlers. Queues are setup as DTC. The interesting thing is, though I get this warning message in QA - it successfully retries N number of times and places the message in the error queue. However, in Production, (in few cases - I haven't seen this happening consistently), it just tries processing the message once and it stops. It didn't put the message in the error queue or neither it retired N Number of times nor it put the message back in the queue. I don't really see the difference between QA and Prod environment, its the same code base, and we give permission to queues using build scripts.

Here's the stack trace NServiceBus.Unicast.Transport.Transactional.TransactionalTransport - Failed raising 'transport message received' event for message with ID=1fb282b5-7a9e-41ea-834a-5f6767273324\195311762 NServiceBus.Unicast.Transport.TransportMessageHandlingFailedException: Exception of type 'NServiceBus.Unicast.Transport.TransportMessageHandlingFailedException' was thrown. at NServiceBus.Unicast.UnicastBus.DispatchMessageToHandlersBasedOnType(IBuilder builder, IMessage toHandle, Type messageType) in d:\BuildAgent-01\work\NServiceBus.Trunk\src\unicast\NServiceBus.Unicast\UnicastBus.cs:line 899 at NServiceBus.Unicast.UnicastBus.HandleMessage(IBuilder builder, TransportMessage m) in d:\BuildAgent-01\work\NServiceBus.Trunk\src\unicast\NServiceBus.Unicast\UnicastBus.cs:line 827 at NServiceBus.Unicast.UnicastBus.HandleTransportMessage(IBuilder builder, TransportMessage msg) in d:\BuildAgent-01\work\NServiceBus.Trunk\src\unicast\NServiceBus.Unicast\UnicastBus.cs:line 1026 at NServiceBus.Unicast.UnicastBus.TransportMessageReceived(Object sender, TransportMessageReceivedEventArgs e) in d:\BuildAgent-01\work\NServiceBus.Trunk\src\unicast\NServiceBus.Unicast\UnicastBus.cs:line 975 at System.EventHandler`1.Invoke(Object sender, TEventArgs e) at NServiceBus.Unicast.Transport.Transactional.TransactionalTransport.OnTransportMessageReceived(TransportMessage msg) in d:\BuildAgent-01\work\NServiceBus.Trunk\src\impl\unicast\transport\NServiceBus.Unicast.Transport.Transactional\TransactionalTransport.cs:line 409

I tried dropping the same message in QA to test the scenario, however, QA seems to work (with the warning exception log).

Questions 1) Why would this exception happen? Has anyone seen in their system? Why is it logged only as a WARN? I looked at the code and it seems to come from catch block of Unicast.cs where it is handling "Exception".

2) Any suggestions to resolve / dig into the issue?