first try what you are doing with telnet.
donwload putty and do the telnet with the same queries.
HEAD / HTTP/1.1
Host:
User-agent: Prova1
Connection: close
but in this above sequence there is a small flaws your user-agent and connection wont reach to server the correct syntax would be
HEAD / HTTP/1.1
Host: host_name
User-agent: Prova1
Connection: close
another issue is if you send HEAD request server would be reply only with Header information. to get content you need to send GET request.