If you haven't yet confirmed that a) you are not infected with the Conficker worm and b) that you have the necessary protections in place, do so within the next 36 hours. According to the security experts, Conficker will start phoning home for instructions on April 1, and it's no joke.
Visit the Conficker Working Group for more information. If you can't browse to that site, you may already be infected with Conficker. (Try this link instead, which contains the IP address instead of the domain name.)
Most security vendors provide protection in their most current versions. Update now.
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