Despite repeated alerts, tens of thousands may still lose their Internet service Monday unless they do a quick check of their computers for malware that could have taken over their machines more than a year ago.
The warnings about the Internet problem have been splashed across Facebook and Google. Internet service providers have sent notices, and the FBI set up a special website.
According to the FBI, the number of computers that probably are infected is more than 277,000 worldwide, down from about 360,000 in April. About 64,000 still-infected computers are probably in the United States.
To check whether a computer is infected, users can visit a website run by the group brought in by the FBI: http://www.dcwg.org .
The site includes links to respected commercial sites that will run a quick check on the computer, and it also lays out detailed instructions if users want to actually check the computer themselves.