http://www.msnbc.msn.com/id/46404138/ns/technology_and_science-security/
Microsoft mistakenly flags Google as malicious site
Accidental blacklist for some stems from this month's software 'Patch Tuesday'
If you're using Internet Explorer to browse the Web and wondering why you can't access Google, there's a reason — your computer might think it's harboring malware.
Two of Microsoft's anti-virus programs, Microsoft Security Essentials and its business-market sibling Microsoft Forefront, have been mistakenly flagging Google.com as malicious, leaving millions of customers unable to get to the world's most visited website
This isn't the first time Microsoft has locked horns with Google by accident. Last September, the software titan's anti-virus programs not only marked Google's Chrome browser as malware, but actually removed it automatically from about 3,000 Windows machines.
https://krebsonsecurity.com/2012/02/microsoft-av-flags-google-com-as-malware/
https://krebsonsecurity.com/2012/01/microsoft-worm-author-worked-at-antivirus-firm/
Microsoft: Worm Operator Worked at Antivirus Firm
In a surprise filing made late Monday, Microsoft said a former technical expert at a Russian antivirus firm was the person responsible for operating the Kelihos botnet, a global spam machine that Microsoft dismantled in a coordinated takedown last year.
he was a senior system developer and project manager for Agnitum, a Russian antivirus firm based in St. Petersburg. One of the company’s most popular products is Outpost, a free firewall program.
https://krebsonsecurity.com/2010/03/microsoft-warns-of-internet-explorer-0day/
If you depend on IE for browsing the Web, upgrade to IE8 if possible. Otherwise, consider switching to an alternative browser, particularly something like Firefox with an add-on that blocks scripts by default, such as Noscript or Request Policy. Yes, these add-ons take a bit getting used to, but from where I sit, allowing Javascipt and Flash to load unrestricted as you browse the web is simply unsafe on today’s Internet.