WCF integration for both clients and services requires the Autofac.Wcf NuGet package
<serviceHostingEnvironment aspNetCompatibilityEnabled="true" multipleSiteBindingsEnabled="true">
<serviceActivations>
<add factory="Autofac.Integration.Wcf.AutofacServiceHostFactory, Autofac.Integration.Wcf"
relativeAddress="~/Service1.svc"
service="TestService.Service1, TestService" />
</serviceActivations>
</serviceHostingEnvironment>
var builder = new ContainerBuilder();
builder.RegisterType<Service1>();
AutofacHostFactory.Container = builder.Build();