Communication channel error

Hi All,

I am getting an error in my communication channel such that ...

Message processing failed. Cause: com.sap.aii.af.ra.ms.api.RecoverableException: Error during variable substitution: com.sap.aii.adapter.file.varsubst.VariableDataSourceException: The following variable was not found in the message payload: date_processing: com.sap.aii.adapter.file.configuration.DynamicConfigurationException: Error during variable substitution: com.sap.aii.adapter.file.varsubst.VariableDataSourceException: The following variable was not found in the message payload: date_processing

can any one pls guide me regarding this .

Thanks in advance

Krushi