I was checking the documentation about MM-SUS and it always says that Order Response can be optional; however, when I send a PO from R/3 to SUS is always needed.
Vendors have to confirm the PO in order to create the ASN.
I tried changing the inforecord, if field "Ackn.Rqd" is not selected, I can't create any follow-on document (POR and ASN) in SUS, but if I select it and field "Conf.Ctrl" has the value "0004" (only ASN), the inbound idoc gets a error (error 51). So, only the combination "Ackn.Rqd" selected and "Conf.Ctrl" with value "0001" (Confirmation and ASN) is working correctly.
How can be the Order Response optional?