What are the reasons that cause ServiceActivationException?

The error says that you don't have a binding configuration for "basicHttpBinding" named "basicHttpBinding". Since you didn't post your complete config, and the error message says that, I'll assume that this is the case.

The config below (under <system.serviceModel>) has two binding definitions under <basicHttpBinding>, one for each binding configuration you have in your endpoint declarations. You should have something similar in your config as well.

<services>
    <service name="xxxx.AppServer.Host.Services.yyyyy.zzzzPlugInService"
             behaviorConfiguration="MetadataBehavior"
            xdt:Locator="XPath(//service[@name='xxxx.AppServer.Host.Services.yyyy.zzzzPlugInService'])"
            xdt:Transform="Replace">
        <endpoint address=""
                  binding="basicHttpBinding" 
                  bindingConfiguration="basicHttpBinding"
                  contract="xxxx.Shared.IntegrationServices.yyyy.IzzzzPlugInService">
            <identity>
                <dns value="localhost"/>
            </identity>
        </endpoint>
        <endpoint address="" 
                  binding="basicHttpBinding" 
                  bindingConfiguration="basicHttpsBinding" 
                  contract="xxxx.Shared.IntegrationServices.yyyy.IzzzzPlugInService">
            <identity>
                <dns value="localhost"/>
            </identity>
        </endpoint>
        <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange"/>
    </service>
</services>
<bindings>
    <basicHttpBinding>
        <binding name="basicHttpBinding" />
        <binding name="basicHttpsBinding">
            <security mode="Transport" />
        </binding>
    </basicHttpBinding>
</bindings>