Sounds like your inbound thread protocol is receiving but it’s in a format it does not understand. Check your protocol pdl. Are you using mlp_tcp.pdl? It may need to be configured in the inbound thread definition. You stated that you are using the tcpip protocol but you may need to use pdl-tcpip instead. If it worked in before, ask the vendor if they change the inbound msg. The vendor may have them configured differently. Compare the before and after inbound msg in hex to really see what has changed.
