MVC站点在VS中工作但在IIS7中为null异常

Question

我一直在研究一个MVC 4应用程序，当我在visual studio上运行它时可以工作，但是当我将它部署到IIS 7时，我得到一个空引用异常。一旦页面尝试加载，就会立即发生错误。

我已经尝试了这个solution，但它没有效果。

堆栈跟踪显示：

  

[NullReferenceException：对象引用未设置为对象的实例。]      MedicalPractitionerPartnership.Controllers.HomeController.Index（）+856      lambda_method（Closure，ControllerBase，Object []）+78      System.Web.Mvc.ReflectedActionDescriptor.Execute（ControllerContext controllerContext，IDictionary 2 parameters) +241 System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary 2个参数）+38      System.Web.Mvc.Async.AsyncControllerActionInvoker.b__36（IAsyncResult asyncResult，ActionInvocation innerInvokeState）+11      System.Web.Mvc.Async.WrappedAsyncResult 2.CallEndDelegate(IAsyncResult asyncResult) +138 System.Web.Mvc.Async.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3c() +111 System.Web.Mvc.Async.<>c__DisplayClass45.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3e() +452 System.Web.Mvc.Async.<>c__DisplayClass30.<BeginInvokeActionMethodWithFilters>b__2f(IAsyncResult asyncResult) +15 System.Web.Mvc.Async.<>c__DisplayClass28.<BeginInvokeAction>b__19() +37 System.Web.Mvc.Async.<>c__DisplayClass1e.<BeginInvokeAction>b__1b(IAsyncResult asyncResult) +241 System.Web.Mvc.Controller.<BeginExecuteCore>b__1d(IAsyncResult asyncResult, ExecuteCoreState innerState) +29 System.Web.Mvc.Async.WrappedAsyncVoid 1.CallEndDelegate（IAsyncResult asyncResult）+111      System.Web.Mvc.Controller.EndExecuteCore（IAsyncResult asyncResult）+53      System.Web.Mvc.Async.WrappedAsyncVoid 1.CallEndDelegate(IAsyncResult asyncResult) +19 System.Web.Mvc.MvcHandler.<BeginProcessRequest>b__4(IAsyncResult asyncResult, ProcessRequestState innerState) +51 System.Web.Mvc.Async.WrappedAsyncVoid 1.CallEndDelegate（IAsyncResult asyncResult）+111      System.Web.CallHandlerExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute（）+606      System.Web.HttpApplication.ExecuteStep（IExecutionStep step，Boolean＆amp; completedSynchronously）+288