title: wcf - No connection could be made because the target machine actively refused it
body: <p>I created a WCF service.  It worked well yesterday.  When I entered service address, I got message returned as expected.  However, when I run it today, I received error message:
  In IE: [Fiddler] The socket connection to localhost failed. 
  ErrorCode: 10061. No connection could be made because the target machine actively refused it [::1]:47423 
  In Firefox: Firefox can't establish a connection to the server at the site
  In Fiddle2: HTTP: 502
  How to solve this problem?  Thanks.</p>