wcf. end point

This app.config is resided in my c# class library. and I have class library called service.cs


I also have web application in c# and try to called service.cs (of course I added reference inside of the web app)
and I have alert about "Could not find default endpoint element that references contract"

so I create another web application project and add web reference directly and the webconfig is exactly the same. there is no error and I can call as usual.
What did I do wrong?

<?xml version="1.0" encoding="utf-8"?>
<configuration>
    <system.serviceModel>
        <bindings>
            <basicHttpBinding>
              <binding name="BasicHttpBinding_IQuotingService" allowCookies="true" maxBufferSize="20000000" maxReceivedMessageSize="20000000">
                <readerQuotas maxDepth="32" maxStringContentLength="200000000" maxArrayLength="200000000"/>
                <security mode="Transport"/>
              </binding>
            </basicHttpBinding>
        </bindings>
        <client>
            <endpoint address="abc.svc" 
                      binding="basicHttpBinding" 
                      bindingConfiguration="BasicHttpBinding_IQuotingService" 
                      contract="NGICService.IQuotingService" 
                      name="BasicHttpBinding_IQuotingService"
                      />
        </client>
    </system.serviceModel>
<startup><supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5.1"/></startup></configuration>

Select allOpen in new window