IIS error hosting WCF Data Service on shared web host

Question

My client has a website hosted on a shared web server. I don't have access to IIS. I am trying to deploy a WCF Data Service onto his site. I am getting this error:

IIS specified authentication schemes 'IntegratedWindowsAuthentication, Anonymous', but the binding only supports specification of exactly one authentication scheme. Valid authentication schemes are Digest, Negotiate, NTLM, Basic, or Anonymous. Change the IIS settings so that only a single authentication scheme is used.

I have searched SO and other sites quite a bit but can't seem to find someone with my exact situation. I cannot change the IIS settings because this is a third party's server and it is a shared web server. So my only option is to change things in code or in the service config. My service config looks like this:

<system.serviceModel xdt:Transform="Insert">
  <serviceHostingEnvironment>
    <baseAddressPrefixFilters>
      <add prefix="http://www.somewebsite.com"/&gt;
    </baseAddressPrefixFilters>
  </serviceHostingEnvironment>
  <bindings>
    <webHttpBinding>
      <binding name="{Binding Name}" >
        <security mode="None" />
      </binding>
    </webHttpBinding>
  </bindings>
  <services>
    <service name="{Namespace to Service}">
      <endpoint address="" binding="webHttpBinding" bindingConfiguration="{Binding Name}" contract="System.Data.Services.IRequestHandler">
      </endpoint>
    </service>
  </services>
</system.serviceModel>

As you can see I tried to set the security mode to "None" but that didn't seem to help. What should I change to resolve this error?