//NOTE: Substring [0] after MessageHeader
strXPATH = "/*[local-name()='MyRoot' and namespace-uri()='']/*[local-name()='MESSAGE' and namespace-uri()='']/*[local-name()='MESSAGE_HEADER' and namespace-uri()=''][1]/*[local-name()='FILE_NAME' and namespace-uri()='']/text()";
xpath(msgCanonical, strXPATH) = strFileRcvdName;