Would you like help getting started with a legal, modern alternative like ns-3 or OMNeT++? I can point you to tutorials and installation guides.
was a powerful network simulation tool originally developed by OPNET Technologies, later acquired by Riverbed Technology. Version 17.5 is an older release (circa 2012–2013). Riverbed has since discontinued OPNET Modeler, replacing it with Riverbed Modeler (now part of SteelCentral). Download Opnet Modeler 17.5 Full Version
I understand you're looking for information about OPNET Modeler 17.5. However, I must provide some important context first: Would you like help getting started with a