Harry Reeve writes: "I recently tried connecting a Linux computer to my XP system. I have a Netgear modem/router model DG632. In my attempts to get them talking, I must have made some bad configuration changes.
"With just the XP PC connected, I can access email and update AVG and Spybot. However, with the Linux box connected, I can't access any website. Whatever I enter into the address bar, it tries to connect to site 18.104.22.168."
I can't help with Linux technical issues, Harry, as I have had little experience of it, but what you describe looks as though it is an error with the DNS (domain name system) configuration. In your network, the Netgear router should be the DNS server and both of your PCs should use it. When the Netgear's DNS server doesn't know how to resolve an address such as www.techadvisor.co.uk into a numeric IP address, it will ask your ISP's DNS server for the answer. If that doesn’t know, it will ask one higher up the chain and so on.
My guess is that your Linux system has a DNS server running, which tries to take over whenever the PC is connected. This DNS server isn't properly configured and doesn't know where to get answers to addresses it doesn't know and, when it starts up, it doesn't know anything. Hence, it is returning these invalid addresses.
Disable the DNS server on your Linux box and get it to use your router for its DNS provider.
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