2580307 - Cannot decrypt secret key error in PI Elster scenario

• You have an existing Process Integration or Process Orchestration Elster sceanrio (interface)
• This scenario was previously working well, but suddenly starts to fail with the error (visible in the Audit Log in PI):
  Error in processing caused by: com.sap.aii.af.mp.module.ModuleException: call to messaging system failed: com.sap.aii.af.ra.ms.api.DeliveryException: XIAdapterFramework:GENERAL:com.sap.aii.af.ra.ms.api.DeliveryException: SsfInvalidDataException in Method: MessageProcessorElsterReceiveResponseModul: decryptEnvelopedData( InputStream ).
  The data couldn't be decrypted.
  Message: Cannot decrypt secret key. To-String: com.sap.security.core.server.ssf.SsfInvalidDataException: Cannot decrypt secret key.
  caused by: com.sap.aii.af.ra.ms.api.DeliveryException: XIAdapterFramework:GENERAL:com.sap.aii.af.ra.ms.api.DeliveryException: SsfInvalidDataException in Method: MessageProcessorElsterReceiveResponseModul: decryptEnvelopedData( InputStream ).
  The data couldn't be decrypted. Message: Cannot decrypt secret key. To-String: com.sap.security.core.server.ssf.SsfInvalidDataException: Cannot decrypt secret key.

• PI Release Independent
• SAP NetWeaver
• SAP Process Integration

Process Integration 7.0, PI 7.0, PI 7.01, PI 7.02, Process Integration 7.10, PI 7.10, Process Integration 7.11, PI 7.11, Process Integration 7.30, PI 7.30, Process Integration 7.31, PI 7.31, Process Orchestration 7.40, PI 7.40, PO 7.40, Process Orchestration 7.50, PI 7.50, PO 7.50, NetWeaver, XI , KBA , BC-XI-CON-ELS , HR/FI Elster Module for PI , PY-DE-BA , Business to Administration , Problem