On Monday, July 9, tens of thousands, possibly millions, of computer users around the world began to lose most of their Internet access — thanks to the U.S. government.
Why this is happening is a long, complicated story that we've detailed several times on SecurityNewsDaily. It involves an Eastern European gang of online criminals, a piece of malware called DNSChanger, a dramatic international police operation and a judge's ruling.
For the full details, check out our recently updated FAQ:
Fortunately, most people will not be affected. To find out whether you might be, simply point your home or office computer to this website: http://dns-ok.us/ (Mac users need to check this too.)
If you get an image with a green background, and text including the phrase "DNS Resolution = GREEN," you're OK and have nothing more to worry about. You can stop reading this now.
If you get a red image, you will eventually lose your ability to reach websites and use email. Some Internet service providers are keeping infected machines online for a period of time — AT&T reportedly will be covering its customers until the end of the year, while Verizon will be doing so until the end of July — but the end will come.
To restore your ability to access the Internet without a helping hand, the first thing you need to do is set aside a couple of hours to run a full-system anti-virus scan. Don't have anti-virus software? Here's a helpful list.
Once the full-system scan is done, quarantine or purge any malware you may find on your PC or Mac.
Then you've got to check computer's DNS (Domain Name System) settings. Here's a video from Sophos Labs in England to show you how:
Once that's done, go to http://dns-ok.us/ again.
Green? You're in the clear.
Red? Uh-oh. Your home or office router may be infected.
Contact the router manufacturer for help on how to clean it. If your router's more than five years old, consider buying a new one. Most are under $100.
To avoid becoming infected by malware, install and use anti-virus software, keep your applications and operating system completely updated, turn on your computer's firewall and spend most of your computer time as a "limited" user who can't change the machine's settings.