I seem to have networking problems with my Dell mini-10 at my holiday resort in France.

They have a modem router called a Livebox. I managed to 'hack' into it (default password) and tried changing security settings, but whatever I chose, even no security, it would not let me in.

It's not the first time I've hard wireless network problems with my Dell-mini 10. I also was unable to connect to my father's router, unless WPA2-PSK was chosen.

What could the problem be?