Having trouble connecting to the internet

Hello,
My wife is running a computer on xp, and as of yesterday we can no longer connect to the internet on it. It claims the network connections are fine. I've tried the "Repair" option for the "local area connection" but get the error message: "Windows could not finish repairing the problem because following action cannot be completed: Clearing the DNS cache. For assistance, contact the person who manages your network." Well, that's me, and I don't know what to do. Thanks.