More likely it's an attempt to seize control of your PC, then try to sell you the ''solution'' for the damage they cause, and/or rope your machine into a spammer botnet. There is a great wave of these fake MicroSoft techs currently calling from South Asia, easily identified by their broken English, ridiculous claims, and sheer lack of system knowledge.
Resident47 Jun 11th, 2012
Apparently will call stating that your " OS and computer." ( Won't offer what brands or system running )is experiencing problems blah,blah,blah,fail, and will crash!!! Unless you go right now and do enter commands as he says onto your computer.
Cannot tell you what company he (they) represent; but has a great number you could call back to ( didn't ask sorry ) to either charge YOU a bundle or most likely a front for a great advice. NOT....