MVC 4 Can't fix the error The type 'System.Web.Mvc.WebViewPage <TModel> exists in the elements - asp.net-mvc-4

Question

after moved my MVC 4 project from VS 2012 to VS 2013 Community I get the following error (in the LogIn.cshtml page).
CS0433: The type 'System.Web.Mvc.WebViewPage "exists in the elements c:\Windows\Microsoft.NET\assembly\GAC_MSIL\System.Web.Mvc\v4.0_4.0.0.0__31bf3856ad364e35\System.Web.Mvc.dll and c:\Windows\Microsoft.NET\assembly\GAC_MSIL\System.Web.Mvc\v4.0_3.0.0.0__31bf3856ad364e35\System.Web.Mvc.dll
I deleted all files from C:\Windows\Microsoft.NET\Framework\v4.0.30319\Temporary ASP.NET Files, cleaned the solution but the problem remains. How to fix it ?
EDIT
The Test project used the MVC 3, that was the reason

Answer 1

If you have already tried the above solutions and are still getting the same problem then try this one->
Go to your project folder and in there locate the bin folder --> Remove System.Web.Mvc.dll and System.Web.Mvc.xml from there.

Answer 2

You could check in your web.config files.
Check if the version is the same as you're using as reference.
Application web.config file:
<add assembly="System.Web.Mvc, Version=3.0.0.1, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
and
<bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.1" />
And the Views web.config file:
<add assembly="System.Web.Mvc, Version=3.0.0.1, Culture=neutral, PublicKeyToken=31BF3856AD364E35" namespace="System.Web.Mvc" tagPrefix="mvc" />
In my example, my MVC dll is the version 3.0.1. But Visual Studio built my solution as if it were 3.0.0. So I had to map the references in the web.config files to 3.0.1.

Answer 3

Check if you are referencing both DLLs to your project.
Your project is reading in two assemblies that might be referenced in your project:
System.Web.MVC version 4.0.0.0 and in System.Web.MVC version 3.0.0.0

Answer 4

In your root web.config, near the bottom, you will have something like the following:
<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35"/>
<bindingRedirect oldVersion="4.0.0.0-4.0.0.1" newVersion="4.0.0.1"/>
</dependentAssembly>
</assemblyBinding>
</runtime>
For me, I simply changed the 'oldVersion' number to 1.0.0.0-4.0.0.1 so that this application will always use the 'newVersion'.