Response code is 403 from wm.ip.chem:receive

Any ideas as to what can result in response code 403 from pub.prt.tn:handleBizDoc when submitting a document to TN using http, apart from an inactive partner profile?

I am trying to implement Chem eStandards Module 6.0 with CIDX standard 2.0.2 using the WM supplied process models (2 action)on a single IS instance (simulating a hub with 2 trading partners - cf the WM shipped sample).

The Buyer(initiator) process works OK to the point where it is waiting for the external response document. The Seller(responder) process works OK to the point where it tries to send the response document (i.e. the payload mapping & validation steps are successful). The External 42 Order Response 2.0.2 document appears in the TN console for the Seller and then for the Buyer (5 times � once for each retry). But the initiator side of the conversation continues to wait (until the wait step expires), while the responder side fails at the send step. The process appears to be failing in the wm.ip.chem:receive service.

The error message I am seeing is: com.wm.lang.flow.FlowException: wm.ip.cm.handlers:send(): In service wm.ip.trp:http: Retry 5 of 5: Failed to send data using protocol http. The response code is 403

Are you using the WM reverse invoke server?