我也有同样的问题。我在类库中使用WCF服务，并从windows应用程序项目调用类库。但我是忘记改变<系统。serviceModel>在windows应用程序项目的配置文件中。类库app.Config文件的serviceModel>。 解决方案:将外部项目的配置与类库的wcf配置相同。

“如果在类库中调用服务，并从另一个项目调用类库，则可能出现此错误。” 在这种情况下，如果是winapp或web，则需要将WS配置设置包含到主项目app.config中。如果它是一个web应用程序，就配置它。这是即使使用PRISM和WPF/Silverlight的方式。”

是的，但是如果你不能改变主项目(例如Orchard CMS)，你可以在你的项目中保留WCF服务配置。

你需要用客户端生成方法创建一个服务助手:

public static class ServiceClientHelper
{
    public static T GetClient<T>(string moduleName) where T : IClientChannel
    {
        var channelType = typeof(T);
        var contractType = channelType.GetInterfaces().First(i => i.Namespace == channelType.Namespace);
        var contractAttribute = contractType.GetCustomAttributes(typeof(ServiceContractAttribute), false).First() as ServiceContractAttribute;

        if (contractAttribute == null)
            throw new Exception("contractAttribute not configured");

        //path to your lib app.config (mark as "Copy Always" in properties)
        var configPath = HostingEnvironment.MapPath(String.Format("~/Modules/{0}/bin/{0}.dll.config", moduleName)); 

        var configuration = ConfigurationManager.OpenMappedExeConfiguration(new ExeConfigurationFileMap { ExeConfigFilename = configPath }, ConfigurationUserLevel.None);
        var serviceModelSectionGroup = ServiceModelSectionGroup.GetSectionGroup(configuration);

        if (serviceModelSectionGroup == null)
            throw new Exception("serviceModelSectionGroup not configured");

        var endpoint = serviceModelSectionGroup.Client.Endpoints.OfType<ChannelEndpointElement>().First(e => e.Contract == contractAttribute.ConfigurationName);
        var channelFactory = new ConfigurationChannelFactory<T>(endpoint.Name, configuration, null);
        var client = channelFactory.CreateChannel();
        return client;
    }
}

并使用它:

using (var client = ServiceClientHelper.GetClient<IDefaultNameServiceChannel>(yourLibName)) {
                ... get data from service ...
            }

详见本文。

我曾经遇到过这个问题。这是因为我还在开发使用WCF服务的接口。我配置测试应用程序和继续开发。然后在开发中，我改变了一些服务的名称空间。所以我再次检查了“系统”。serviceModel ->客户端->端点->合同”。配置匹配WCF类。那么问题就解决了。

There seem to be several ways to create/fix this issue. For me, the CRM product I am using was written in native code and is able to call my .NET dll, but I run into the configuration information needing to be at/above the main application. For me, the CRM application isn't .NET, so I ended up having to put it in my machine.config file (not where I want it). In addition, since my company uses Websense I had a hard time even adding the Service Reference due to a 407 Proxy Authentication Required issue, that to required a modification to the machine.cong.

代理解决方案:

为了让WCF服务引用工作，我必须从我的DLL的app.config复制信息到主应用程序配置(但对我来说是machine.config)。我还必须将端点信息复制到同一个文件中。一旦我这么做了，它就开始为我工作了。

对使用服务的非库应用程序进行单元测试可能会导致此问题。

The information that others have entered addresses the root cause of this. If you are trying to write automated test cases and the unit you are testing will actually invoke the service interface, you need to add the service reference to the test project. This is a flavor of the application using library type of error. I did not immediately realize this though because my code that consumes the interface is not in a library. However, when the test actually runs it will be running from the test assembly, not the assembly under test.

向单元测试项目添加服务引用解决了我的问题。

好的。我的情况有点不同，但最后我找到了解决办法: 我有一个控制台。exe -> DLL ->调用WS1 -> DLL ->调用WS2

我已经按照建议在Console.EXE.config中配置了WS1和WS2的服务模型。没有解决问题。

但它仍然没有工作，直到我将WS2的WebReference也添加到WS1，而不仅仅是添加到实际创建和调用WS2代理的DLL中。