I have heard numerous reports recently of homes receiving phone calls from representatives of Microsoft, claiming that their computer is hacked or infected with a virus and requires immediate service. To my knowledge, Microsoft does not make phone calls to end user customers in this fashion, and so they are very likely a scam.
Kim Komando shares an email sent to her describing one of these tech support phone call scams in detail, and gives some tips about what you can do if you receive such an unsolicited phone call.
~Ted Eiler
To Article: Spot and avoid a dangerous phone tech support scam | Komando.com.