SAP Message UC901 - Receiver structure for sender structure &1 cannot be determined

Diagnosis
The receiver structure cannot be read from the ABAP Dictionary.

System Response
The rules for the sender structure cannot be converted.

Procedure
Check whether the ABAP Dictionary structure for the receiver is activeand saved in the ABAP Dictionary. If not, activate and save it. Thenexecute program RKCXPR40 again.

128009Upgrade to 4.X: Error messages in CHK_POSTUP