"Companies that receive daily updates of good anti-virus software could nip this thing in the bud, " Grossman says.

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Companies often do not realize that an employee has disabled the anti-virus software or fail to stay on top of available updates, he said.

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And, if you read the fine print, you will discover that in order to get virus signature updates ( a requirement for any AV product), you must have Software Assurance!

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Similarly Kaspersky Labs' anti-virus software lets one copy update itself via the net and then copies on other PC can download updates from that machine via the home network.

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He said people should sign up for automatic updates, make sure the applications they use are regularly patched, use anti-virus software and run a firewall.

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