I finally got a new client. Aren't you proud of me?

They have an issue that I've never seen before. Their web site and only
their web site has a bunch of casino **** pasted to the top. If you go
to oakbrew.com it looks correct. If you do that on their lan, you get
the casino stuff. If you Google oakbrew then "Play The Web Best Casino
Games" is the first hit.

Their web guy is looking into the Google side of things. I'm supposed to
clean up the lan. We replaced their cheap Netgear router, no joy. We
pointed them at a new DNS server, no joy. I took one of their computers
to our shop to see if it still happened. It didn't.

It's a Windows peer to peer network.

I purposely used their name so that you could enjoy their brew, boosting
their sales and making it easier for them to afford me.

I'm looking for ideas.