Last year, the FBI shut down some hackers who were infecting computers worldwide with "DNS Changer" malware that redirects Internet users to some malicious servers. The malware can also disable antivirus software, making you even more vulnerable. And, it can corrupt the router you may use to connect to the Internet.
To give people time to disinfect their computers without losing their ability to use the Internet, the FBI set up a group of clean "safety net" servers in place of the malicious ones. Those safety net servers are scheduled to be shut down on Monday, 7/9/2012.
Many Computers May Still be Infected
AP is reporting that many computers worldwide may still be infected. The FBI believes that about 64,000 computers in the U.S. are still infected, including some belonging to Fortune 500 companies.
If your computer is infected, you could lose Internet service, including access to your email, Twitter, Facebook, Google, etc. You would then need to clean your computer manually.
How to Check Your Computer
The FBI has also set up a web page to help you check if your computer is infected. You can run their automated software or you can follow the instructions to check your computer yourself:
Check Your Router Also
Many people and businesses use wired and wireless routers to connect their individual computers to the Internet. DNS Changer malware can also change the IP address that your router uses to connect to the Internet, especially if you never changed the router's default username and password.
You should check to see if the IP address that your router uses has been changed. If it has, you'll need to reset the router to its default settings. Check your router's instructions for doing so. But make sure that you check (and disinfect if necessary) all machines that connect to the router first, whether wired or wireless.
This would also be a good time to change the default username and password to make it harder for malware to modify your router's settings in the future.