How can I combine the WCF services config for both http and https in one web.config?

Well, one problem with your combined config is that your two endpoints are on the same address – that won’t work.

If you’re hosting in IIS, then your server, virtual directory and the *.svc file needed will determine your basic address – it’ll be something like:

http://yourservername/VirtualDirectory/YourService.svc

If you want to have two endpoints, at least one of them needs to define a relative address:

<services>
    <service name="MyNamespace.MyService" 
             behaviorConfiguration="MyServiceBehavior">
       <endpoint 
           address="basic" 
           binding="basicHttpBinding" 
           contract="MyNamespace.IMyService"/>
       <endpoint 
           address="secure" 
           binding="basicHttpBinding" bindingConfiguration="HttpsBinding"  
           contract="MyNamespace.IMyService"/>
    </service>
</services>

In this case, you’d have your HTTP endpoint on:

http://yourservername/VirtualDirectory/YourService.svc/basic

and your secure HTTPS endpoint on:

https://yourservername/VirtualDirectory/YourService.svc/secure

Furthermore: your secure endpoint uses a HttpsBinding configuration – but you’re lacking such a binding configuration – all you have is:

<bindings>
  <basicHttpBinding>
    <binding name="HttpBinding">
      <security mode="None">
        <transport clientCredentialType="None"></transport>
      </security>
    </binding>
  </basicHttpBinding>
</bindings>

You need to add the HttpsBinding configuration!!

<bindings>
  <basicHttpBinding>
    <binding name="HttpBinding">
      <security mode="None">
        <transport clientCredentialType="None"></transport>
      </security>
    </binding>
    <binding name="HttpsBinding">
      <security mode="Transport">
          <transport clientCredentialType="Windows" />
      </security>
    </binding>
  </basicHttpBinding>
</bindings>