CFGR-519 — Incorrect configuration directive found
The configuration parser has found an item or a section that is known but incorrect in given point of configuration.
The reason for such a misunderstanding is that some general feature is disabled when deriving particular variation. For example, the PLUG-TO item is allowed in general SYSTEM.ACL, but in the SMTP-PROXY.SESSION-ACL this item is not valid. Thus, when this item is used there, you will see this error message.
See the proper configuration (section 5) manual page and correct the error. You will probably need to move the special feature from the general definition into particular (e.g. proxy) sections where it is required.