http://developers.de/blogs/damir_dobric/archive/2010/11/19/invalidoperationexception-when-starting-the-service-host.aspxWhen trying to create the service host instance of the WCF service like: ServiceHost svcHost = new ServiceHost (typeof(MyService)); svcHost.Open(); you might get following exception:   Service 'UnitTests.SbbNetCoreTest+TestServiceCallback'enCommunityServer 2008 SP1 (Build: 30619.63)