TrafCI on Windows fail to connect to server without specifying port number though port number is default value 23400

Run trafci.cmd,
1 When input the Host Name/IP Address without port-number, it returns me an error 29113, Connection refused.
2 When input the Host Name/IP Address with port-number(23400) which is the default port-number, connection successful.

See log below,
Welcome to Apache Trafodion Command Interface
Copyright (c) 2015-2016 Apache Software Foundation

Host Name/IP Address: 192.168.0.16
User Name: trafodion
Password:
Password:

• • • ERROR[29113] error while opening socket. Cause: Connection refused: connect

Host Name/IP Address: 192.168.0.16:23400

Connected to Trafodion