Most likely, the sample code cannot connect to Service Objects…
Most likely, the sample code cannot connect to Service Objects. Many environments will not allow you to connect out on port 80 or will clip out XML data from these requests/responses.
The easiest way to check for this is to open a browser on the machine running the sample code. In your browser, navigate to: https://trial.serviceobjects.com/lvi/
Then test the ValidateLeadInternational operation with your trial key. If you get a browser error or get no data back, then the sample code isn’t able to connect, either. Contact your systems administrator to resolve why you are not able to connect to Service Objects.