I get called, no one is ever on the other end!

I received a call from this number and when I answered was an international call from my cousin in Spain.

Received a call Nov. 28/11 at approx. 5:04 pm asking if we had "windows" on our computer and wanted info about it and they could fix it.  I asked for their phone number that they were calling from and he said they did not have a return number.  When questions as to why someone working on behlalf of  "windows" did not have a return number the phone went dead.  Tonight (Nov. 29/11) at approx. 4:28 pm a call came in from a local number (705) 749-5676 asking about the same thing and when we tried to contact them right back the number was "no longer in service".  Then 1 minute later another long distance call "unknown name and unknown number" came from same people.  How do we stop this crap.

fuzzy staticy message saying "hello", called back no one there.

called me this afternoon, no name no message just the numbner