Data Correlation: Failed Substitution\nReference[%1]\nSubstitution[%2]\n\nDetails:\n\nA failed reference occurred in a prior request. Since the reference named [%3] was null, we were unable to substitute a new value for the substituter named [%4], original string [%5] at offset [%6] and this request may have failed. Please inspect prior requests for the reference failure and corrective guidance to avoid this in the future.\n\nFor more information search the help for the data correlation topics.
A reference for an expected data substitution is null.
To find the failed reference, open the test and go to the substitution site. Right-click the substitution site and select Go To > Reference. When troubleshooting failed references, start with the first error message. The first failed reference can cause subsequent failed references. Search the test log "for unable to extract" to find the first error message.\n\nExamine the request that generated the response. The request contains a value that might need to be correlated. For example, the request might contain a username that must be unique to play back the test successfully. In that case, use a dataset to provide a list of unique username values. You might need to manually correlate a value by using the Test Data Sources view. Values that typically are correlated include timestamps, dates, ids, and other alphanumeric strings.\nIf you no longer need the data correlation mentioned in the message, remove that data correlation from the test.