NServiceBus - How to configure bus to allow WindowsIdentity to flow from client

On the client I have setup the bus with ImpersonateSender(true)

My server is configured AsA_Server, which by default should have ImpersonateSender(true)

I'm now trying to retrieve the WindowsIdentity, from inside a Handler

var windowsIdentity = WindowsIdentity.GetCurrent(true);

But this is giving me null.

What am I doing wrong?

Use System.Threading.Thread.CurrentPrincipal instead.

Also, don't set ImpersonateSender on the client - it'll send it's credentials regardless.