Lee, all, We tracked down the issue to an attribute variable I was using to put into the json. It had unescaped/hidden characters (\n) that where causing the JOLT processor to fail; however like you, it would work via the "Advance Editor". I used escapeJson() on the attribute it works it also makes the \n are visible in the flowfile. https://nifi.apache.org/docs/nifi-docs/html/expression-language-guide.html#escapejson Simple Example: [ { "operation": "default", "spec": { "content": "${ext_content:escapeJson()}", <- ext_content attribute contained the issue "date": "${ext_date}", "updateDate": "${ext_updateDate}" } } ] Hope this this helps and saves someone else some time! JF ... View more