"Fooled" may have sounded like you were tricked. No, these infections are miserable drive-by infections where a web site is infected (often through an ad placed on the site via a 3rd party service) and the pop-up that is delivered to you infects your PC if you so much as touch it, even to close it down. The only way to prevent infection is to shut down the browser through Task Manager or reboot the PC, forcing the shut down. There have been reports of some infections happening with *no* interaction from the user at all.
-steve
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