сначала я бы сделал эту конфигурацию в WCF App.config
<endpoint address ="" binding="basicHttpBinding" bindingConfiguration="basicHttp" contract="AddSubService.IService1">
<!--
Upon deployment, the following identity element should be removed or replaced to reflect the
identity under which the deployed service runs. If removed, WCF will infer an appropriate identity
automatically.
-->
<identity>
<dns value="localhost"/>
</identity>
</endpoint>
<!-- Metadata Endpoints -->
<!-- The Metadata Exchange endpoint is used by the service to describe itself to clients. -->
<!-- This endpoint does not use a secure binding and should be secured or removed before deployment -->
<endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"/>
</service>
</services>
<bindings>
<basicHttpBinding>
<binding name="basicHttp" allowCookies="true"
maxReceivedMessageSize="20000000"
maxBufferSize="20000000"
maxBufferPoolSize="20000000">
<readerQuotas maxDepth="32"
maxArrayLength="200000000"
maxStringContentLength="200000000"/>
</binding>
</basicHttpBinding>
</bindings>
Затем попробуйте обновить ссылку на стороне ASP.NET, которая вызывает WCF в web.config, чтобы убедиться, что конечная точкаизменился на тот же.