In some cases below error would be raised while starting a BW process which starts with KafkaReceiveMessage activity.
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-{ActivityName=KafkaReceiveMessage}.
...
com.tibco.bx.core.faults.BxException: Activity output data validation error. The output data from activity [KafkaReceiveMessage] in process [PROCESS_NAME], module [MODULE_NAME] does not conform to the activity output schema. Value is not a node  Schema=
schema-element({http://www.tibco.com/namespaces/tnt/plugins/receiver+5dc4e68c-55e0-4cd1-8a86-38e0b0c405eb+KafkaReceiverMessageOutput}KafkaReceiverMessageOutput)  {http://www.tibco.com/namespaces/tnt/plugins/receiver+5dc4e68c-55e0-4cd1-8a86-38e0b0c405eb+KafkaReceiverMessageOutput}KafkaReceiverMessageOutput
Sequence
schema-element(topic)  {http://www.w3.org/2001/XMLSchema}string
schema-element(partition)  {http://www.w3.org/2001/XMLSchema}long
schema-element(offset)  {http://www.w3.org/2001/XMLSchema}long
schema-element(key)  {http://www.w3.org/2001/XMLSchema}string
schema-element(message)  {http://www.w3.org/2001/XMLSchema}string
schema-element(headers)  {http://genxdm.org/typed/local-types}bwtype-0
Sequence
schema-element(header)  {http://genxdm.org/typed/local-types}bwtype-1
Sequence
schema-element(key)  {http://www.w3.org/2001/XMLSchema}string
schema-element(value)  {http://www.w3.org/2001/XMLSchema}base64Binary
Sequence
Sequence
Sequence
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Two reasons are identified as of now which can lead such kind error:
1. The "Bootstrap Servers" on the Kafka Connection resource is not set properly. For example leaving the default literal value "host:port" instead of giving the actual Kafka broker information.
2. A Kafka consumer property "security.protocol" is added to the KafkaReceiveMessage activity with value SASL_SSL without having Kerberos authentication enabled.