Orcommn-12004 — Free

– The message size exceeds the maximum allowed by the receiving endpoint or an intermediate gateway.

: The local hostname or server name is not correctly defined in the system's registry or environment settings. Step-by-Step Resolution Guide 1. Configure System Environment Variables orcommn-12004

The problem may not be with Oracle. Check the logs of the system it is trying to communicate with. Look for rejected messages, crashes, or permission errors. – The message size exceeds the maximum allowed