When you start the OpenWindows software it is accessed through the directory /usr/openwin. The OpenWindows software is installed in this location by default. Many applications, for example Calendar Manager, cannot load unless the OpenWindows software is properly installed in /usr/openwin.
If your OpenWindows does not start when you type the command /usr/openwin/bin/openwin, either you do not have the OpenWindows software installed, or it is installed in a directory other than /usr/openwin. See the OpenWindows Desktop Reference Manual, or see your system administrator.