c# – I have the reference, but when I run the CLR it says that the reference is missing


I have this include in my project: System.Web.MVC.Ajax . However, when running the application, I get a runtime error in the web.config file. If I comment out the error line in web.config , the error appears on the bottom line, referring to System.web.MVC.Html . This is the error that appears:

Server Error in Application '/'.

Compilation Error

Description: Error compiling a resource required to fulfill this request. Examine the specific details of the error and modify the source code accordingly.

Compiler Error Message: CS0234: Namespace name or type 'Ajax' does not exist in namespace 'System.Web.Mvc'. Need an assembly reference?

Origin Error:

Line 22: Line 23:
Line 24: //here gives the error. Line 25:
Line 26:

Source File: c:\Projetos_MVC\Sistema.Mvc\Web.config Line: 24

Show Detailed Compiler Output:

Show Full Build Source:

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version: 4.0.30319.34249

What I don't understand is that I have the reference and see the includes of my controller and none are with errors:

using System.Data.Entity;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Mvc;
using System.Web.Mvc.Ajax;

Well this is my route file, it might be useful:

public class RouteConfig
        public static void RegisterRoutes(RouteCollection routes)

                name: "BrandContext",
                url: "{controller}/{action}/{id}",
                defaults: new { controller = "BrandContext", action = "Index", id = UrlParameter.Optional }

And this is my view that I'm starting to create:

    ViewBag.Title = "Index";

<h2>Index - Teste de Partial View</h2>

In ViewBag is giving the following error.

ViewBag do not exist in the current context

I just don't understand what's really going on.

Below my package.config

<?xml version="1.0" encoding="utf-8"?>
  <package id="AutoMapper" version="4.0.4" targetFramework="net45" />
  <package id="EntityFramework" version="6.1.3" targetFramework="net45" />
  <package id="Microsoft.AspNet.Mvc" version="4.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.Razor" version="2.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebApi" version="4.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebApi.Client" version="4.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebApi.Core" version="4.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebApi.WebHost" version="4.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.AspNet.WebPages" version="2.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.Net.Http" version="2.0.20710.0" targetFramework="net45" />
  <package id="Microsoft.Web.Infrastructure" version="" targetFramework="net45" />
  <package id="Newtonsoft.Json" version="4.5.6" targetFramework="net45" />

The web.config file

<?xml version="1.0" encoding="utf-8"?>
  For more information on how to configure your ASP.NET application, please visit
    <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
    <add key="webpages:Version" value="" />
    <add key="webpages:Enabled" value="false" />
    <add key="PreserveLoginUrl" value="true" />
    <add key="ClientValidationEnabled" value="true" />
    <add key="UnobtrusiveJavaScriptEnabled" value="true" />
    <httpRuntime targetFramework="4.5" />
    <compilation debug="true" targetFramework="4.5" />
        <add namespace="System.Web.Helpers" />
        <add namespace="System.Web.Mvc" />
        <add namespace="System.Web.Mvc.Ajax" />
        <add namespace="System.Web.Mvc.Html" />
        <add namespace="System.Web.Routing" />
        <add namespace="System.Web.WebPages" />
    <validation validateIntegratedModeConfiguration="false" />
      <remove name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" />
      <remove name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" />
      <remove name="ExtensionlessUrlHandler-Integrated-4.0" />
      <add name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness32" responseBufferLimit="0" />
      <add name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework64\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness64" responseBufferLimit="0" />
      <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />


Your configuration is quite wrong. An ASP.NET MVC application has two Web.config files, one in the Views directory and one in the root directory. What you did was mix the two.

This here needs to be removed:

        <add namespace="System.Web.Helpers" />
        <add namespace="System.Web.Mvc" />
        <add namespace="System.Web.Mvc.Ajax" />
        <add namespace="System.Web.Mvc.Html" />
        <add namespace="System.Web.Routing" />
        <add namespace="System.Web.WebPages" />

This snippet does not belong to the <system.web> of the root web.config , but to the <system.web.webPages.razor> tag of the web.config of the Views directory.

A correct configuration would be something like:

    <host factoryType="System.Web.Mvc.MvcWebRazorHostFactory, System.Web.Mvc, Version=, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
    <pages pageBaseType="System.Web.Mvc.WebViewPage">
        <add namespace="System.Web.Helpers" />
        <add namespace="System.Web.Mvc" />
        <add namespace="System.Web.Mvc.Ajax" />
        <add namespace="System.Web.Mvc.Html" />
        <add namespace="System.Web.Routing" />
        <add namespace="System.Web.WebPages" />

Note that this setting is for MVC5, not MVC4, which should be your case. Make the settings carefully.

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