If the portquiz link doesn't open, it means something blocks the port.
That may be firefox settings(does open in ff for me, seems unlikely)
The computer firewall,network firewall or your IPS is likely the culprit.
...but the CLI keeping empty when starting the exe directly is weird. In the case it's blocked I would assume a "host wont respond" message.
edit:
Can you open
http://portquiz.net ?
To check if ports are blocked ou could use
nmap,
enter "nmap -p 4000-5000 -Pn portquiz.net" in the zenmap gui(in the program files(x86)/Nmap directory). May take a while..
You should get a overview of the ports in the 4000-5000 range that are blocked and open.