When the PowerCenter Integration Service writes inbound IDocs to the SAP system, SAP does not report status details back to PowerCenter. Therefore, if SAP fails to post an IDoc or if an error occurs after PowerCenter calls SAP, the PowerCenter session log does not contain the reason for the error. However, you may be able to access detailed information from within SAP. If a PowerCenter call to SAP fails, PowerCenter writes the error to the session log.