Reading Biztalk 2006 R2 Documentation about WS-AT, I found: "Transactional submission is available only for one-way receive locations. If a client attempts to submit messages in a transactional scope for a two-way receive location, an exception will be returned back to the client, and no messages will be suspended." "The transactional scope is limited by the MessageBox. For example, a BizTalk orchestration cannot participate in a clientÂ’s transaction. Similarly, a destination endpoint cannot participate in a transaction that is initiated by a BizTalk orchestration." I need to give a response to a client in a WS-AT transactional scope initiated by the client application, but according to this documentation there is no way. Any Idea? Thanks.