I have created a WiFi hotspot for the local community. The problem is, some Russian PC's (Windows XP, Windows Vista and Windows 7) can't get internet connection (We have a lot of bypassing russian fishing vessels / cargo ships). The pc's obtain a valid IP address, and some of them can even manage to send some few packages - But none of them are usable on the network. They all say "Limited internet access" or "???????????? ?????? ? ????????". The thing these PC's have in common is, that they all run a Russian installation of Windows.

No one else has problems with the WiFi hotspot - Danish and English Windows, Linux and OS X all work like a charm.

Can it be, that there is a difference between the danish / english windows installation, compared to the Russian installation?

EDIT START

They can't ping the router (One PC got one response - ONCE), they can't access any sites and Windows newer asks "Is this network public, home or work?".

EDIT END

PS: The hotspot is a airMAX rocket M from Ubiquiti Networks, Inc (www.ubnt.com)