How to protect your PC against Conficker virus

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What this virus could mean for your computer.

Many of us do banking and keep personal financial records on our computers. The day malicious instructions could be issued to an estimated three to 12 million computers and yours could be infected.

The insidious aspect is that Conficker is hard to detect. Like a good soldier, it is lurking inside millions of computers, waiting for orders that will be sent over the Internet.

"It could steal your identity, it could steal your data, and in this economic times, we don't want anything to happening to ourselves as well, but it can also go out and infect other people," said McAfee President and CEO David DeWalt.

DeWalt's company, MCafee in Santa Clara, has surveillance teams deployed, such as a threat center in Aylsbury, England. They've detected that damaging instructions could be issued on April 1st, and it's already april 1st in other parts of the world.

In Silicon Valley, Proofpoint is a company focused on corporate computer systems. Experts there have noticed one clue that Conficker has already infected a machine.

"It'll actually block access to a number of anti-virus sites. The popular ones such as Norton, F-Secure, McAfee, etc, so if you actually try to go to those websites and find that your computer cannot access them while it can access other sites, that's a telltale sign that your computer has been infected with the Conficker worm," said Proofpoint Product Manager Nithin Rao.

Viruses and worms can create major headaches. A virus infected 300 out of 400 computers at the Mount Diablo Unified School District last month.

"It took about three weeks to clean it up for all of our techs. In most cases, many cases, we had to just reformat the computer, just like starting over," said Mount Diablo School District Computer Technician Jim Morrison.

It's widely suspected organized crime could be behind Conficker, trying to steal money.

"Almost 80 percent of the viruses and worms that we've received at our labs are financially motivated, so with the downturn economy, increase in cybercrime, this is a little bit of a state that we're all in today," said DeWalt.

One important note -- Conficker attacks Windows computers, not Macs.