Said calling from California, Global Routing and needed my computer serial number because I have critical viruses on my computer and unless I give them information, in six hours I will not be able to use my computer - said they had all my information although the serial number they gave me is not mine.  Said they have gave me many warnings and they control the main server and will block my operating system.  Could not understand the first person so someone named Michael spoke next.  When I told him I think he's a scammer he got nasty.  After I hung up he called back again - unknown number - but I didn't answer.