XML-HTTP: Activating/Deactivating Inbound Processing 
If you want to receive IDoc XML documents using the HTTP protocol, you need the appropriate inbound processing. This inbound processing is already defined by SAP in the idoc_xml service. To receive IDoc XML documents, you have to activate this inbound processing.
Choose the transaction SICF (Maintenance of the HTTP Service Tree).
Check whether idoc_xml service is active. Choose (active services are black, inactive services are gray).
If you want to use IDoc_XML inbound processing, the service must be active. In the top menu bar, choose .
If you do not want to use IDoc_XML inbound processing, the service must be inactive. In the top menu bar, choose .