In case you haven’t heard, some people will not be able to access web sites on Monday. Technically, in some cases, if they know the site’s IP address, they may be able to access it. But I doubt that any of you will really remember to go to http://184.108.40.206 when you need to look something up (a.k.a. Google.com).
The problem is because of a piece of malware that was distributed starting in 2007. This malware changed the Domain Name Server (DNS) settings on infected computers to point to the servers run by the people responsible for the virus.
DNS is what translates names (like www.google.com) to their IP address, which your computer uses to contact the server that runs the web site.
To make a long story short, the FBI and Internet Systems Consortium took over the servers for the past eight months, so that infected systems could still access web sites via their names – and started a campaign to educate people and have them check their systems.
Those servers are being shutdown on Monday, July 9, 2012. So, if you haven’t already checked your computers, I advise that you do so.
The simplest way is to go to http://www.dns-ok.us/.
PLEASE also make sure that you have an up to date antivirus program and that it is receiving definition updates regularly. This is the best way to make sure that things like this don’t affect you. If you don’t have one (shame on you), try Microsoft Security Essentials (free for personal use / business up to 10 PCs).
More information and references: