Browse to http://<server>:<port>/itp/configure, where <server> is the name of your web server, and <port> is the port on which the web server is configured to listen.
In the general configuration page, you can specify the host name and port for the ITP/Server that ITP/OnLine will use.
When you click the option submit, these settings will be stored in the file config.xml in the ITP/OnLine configuration folder.
Refer to the ITP/OnLine Server Manual for an extended description on the general configuration settings.