Two giants of the Internet want to make sure you can still get to them after July 9.

Google and Facebook are actively scanning the computers of their users to find some of the nearly 1 million people who have been infected with the DNSChanger malware in the U.S. Google is displaying a warning across the top of its search results page, while Facebook has placed a similar warning at the top of its post-login page. If a user’s computer is infected, Google and Facebook will know and display the warning. Users who are not infected will see no warning at all.

With so many computers potentially impacted by the DNSChange malware, it is no surprise that these two mega-sites want to help eliminate it. Any machine afflicted with the DNSChanger will not be able to connect to the Internet after July 9.

As reported by CNet, the whole problem goes back to an online criminal ring from 2007 that was tinkering with computers' settings and then directing users to rogue servers that the criminals had set up. These servers then re-directed users to malicious Web sites. Late last year, the FBI arrested the ring and seized the rogue servers. But since so many infected computers relied on the servers to reach the Internet, the agency opted not to shut them down and instead converted them to legitimate DNS machines. Due to the high cost associated with operating these servers, the FBI has decided to shut them down on July 9, leaving any infected computer that has not been fixed with no way to reach the Internet.

The Google and Facebook warnings offer links to information on how to remove the DNSChange malware. Anyone who thinks he may be a victim is encouraged to run a Google search, or log in to Facebook to find out for sure.