nruddock, your advice may be related to your personal/past experience, but you seem to be ignoring something here... all these folks (myself included) had this happen for the first time today/yesterday... this means that it's likely a common (externally influenced) cause.

I did not download/install anything (rarely ever download freebies ayway).  I tend to agree with pjz99 above - this sounds like something that happened over the network.

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