The server had refused to start a session with the specified client node because the node connected to the server on the server's administrative port. When different port numbers are used for administrative and client sessions, client sessions may be started only on the port used for client sessions.
Server operation continues.
The client option file should be updated to specify the port to be used for client sessions. This is typically specified by TCPPORT option in both client and server option files. The IBM® MVS™ server also uses the ICSPORT option.