Millions of computers across the globe including many in Oklahoma were infected by malware called DNS Changer.
The malware targeted both PCs and Macs, and redirected users away from websites to ones that were deployed by cyber criminals.
The FBI intercepted those servers last year but left them active after tweaking them to disable the advertisements.
The FBI plans to disable the servers on July 9, 2012, which could mean many computer users will suddenly be unable to access the Internet.
The FBI's DNS Changer Working Group has set up a web page that will check if you've been infected with the malware. If you run the test and it comes back green your computer is okay, but the image background flashes red, then you need to take steps to remove it.
To check and clean computers: http://www.dcwg.org