确定我发现这个问题。

在此情况下，具有 ASP.NET模拟：启用在IIS和我的web.config中发生冲突与我所配置的应用程序池标识。 （我认为）。

In this case, having ASP.NET Impersonation:Enabled in IIS and my Web.Config was conflicting with the Application Pool identity I had configured. (I think).

在我设置的应用程序池标识使用适当的帐户验证查询AD，残疾人模拟和剩余的运行时间 Windows身份验证：启用我能得到网站查询AD不传递任何凭据在我的code。

Once I set the application pool identity to run using an appropriate account authenticated to query the AD, disabled Impersonation and left Windows Authentication:Enabled I was able to get the website to query the AD without passing any credentials in my code.