Wifi connection issue at a public hotspot

[usta]

In a public hotspot I see two networks, both without encryption. I can connect with my laptop to both of them and I receive the local IP address and everything looks fine. However, with one network I can surf, while the other one gives me an error message in IE "Network Server not found". Is this the MAC filter blocking me?

[Supreme2k]

What does it matter? Since you are able to surf with one, you don't need the other.

Bottom line is that you have no control over someone else's network, so we wouldn't really have a clue as to why you're blocked.

If you know who owns the network, ask them.

[usta]

Well, the reason is that the network that doesn't allow me the surfing give the strongest signal. The one I'm using now has a very poor signal, so I have to hold my laptop only in a certain position to get the data running.
I curious of the reason, why one can't use a browser, if the IP address, Gateway IP, subnet mask are allocated and the network uses no encryption.

[Supreme2k]

Like you said, mac filter.

or, they may have a terminal-type login (rather than encryption keys). I've seen it used at hotels.

Probably a dozen other reasons (a wireless router with no internet connection, maybe?)