The server was unable to process the request due to an internal error. For more information about the error, either turn on IncludeExceptionDetailInFaults (either from ServiceBehaviorAttribute or from the <serviceDebug> configuration behavior) on the server in order to send the exception information back to the client, or turn on tracing as per the Microsoft .NET Framework 3.0 SDK documentation and inspect the server trace logs.
服务器无法处理请求由于内部错误。有关错误的详细信息，无论是打开IncludeExceptionDetailInFaults（无论是从ServiceBehaviorAttribute或从<serviceDebug>配置行为）的服务器上，以发送异常信息返回给客户端，或者打开跟踪按照Microsoft .NET框架3.0 SDK文档和检查服务器跟踪日志。
遇到上述错误，一般是wcf配置 的 includeExceptionDetailInFaults=false ，会把具体错误隐藏，只要把 includeExceptionDetailInFaults 的值改为true ,然后看具体错误，再具体问题具体分析就ok了。
<system.serviceModel>
<behaviors>
<serviceBehaviors>
<behavior>
<!-- 为避免泄漏元数据信息，请在部署前将以下值设置为 false 并删除上面的元数据终结点 -->
<serviceMetadata httpGetEnabled="true"/>
<!-- 要接收故障异常详细信息以进行调试，请将以下值设置为 true。在部署前设置为 false 以避免泄漏异常信息 -->
<serviceDebug includeExceptionDetailInFaults="true"/>
<dataContractSerializer maxItemsInObjectGraph="2147483647" />
</behavior>
</serviceBehaviors>
</behaviors>
</system.serviceModel>
</configuration>