Receiver IDOC_AAE Acknowledgements

Hi Experts,

   I am doing the scenario like FILE to IDOC_AAE. Here, receiver IDOC_AAE should send back acknowledgment if status error 51 only.

Please send me some configuration steps in ECC.

I have done PI development. , FILE --> PI --> IDOC-AAE (CREMAS) &&  ALEAUD-->PI--> FILE

And done partner profiles as well.

But, once received the inbound idoc CREMAS, outbound idoc ALEAUD is not triggering . Please help me the steps . Thank you.

deva