Error in BPM: "COMMUNICATION FAILURE" during JCo call. Error opening an RFC

hello experts

i am receiving the above error incase of BPM scenario where i am having a Transform step and synchronous RFC step.

i referred to the few threads discussing such problems and was trying to find whether my mapping is correct and i tested my mappings using my payload which looks good.

When looked into the Mapping trace of the BPM "Show container" i found error ""COMMUNICATION FAILURE" during JCo call. Error opening an RFC connection" and it seems that when BPM is attempting to call interface mapping it is throwing this error.

Thanks in advance.

Regards

rajeev