Expression of type 'System.Web.Mvc.MvcWebRazorHostFactory'

Umbraco 4.11 Expression of type 'System.Web.Mvc.MvcWebRazorHostFactory' cannot be used for return type 'System.Web.WebPages.Razor.WebRazorHostFactory

Estou criando uma custom section no Umbraco 4.11 usando Mvc e me deparei com esse problema. 

Expression of type 'System.Web.Mvc.MvcWebRazorHostFactory' cannot be used for return type 'System.Web.WebPages.Razor.WebRazorHostFactory 

Isso aconteceu quando instalei um Package via nuget.

Solução atualize esse trecho na web.config:

<dependentAssembly>
    <assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
    <bindingRedirect oldVersion="1.0.0.0-2.0.0.0" newVersion="2.0.0.0" />
  </dependentAssembly>
  <dependentAssembly>
    <assemblyIdentity name="System.Web.WebPages.Razor" publicKeyToken="31bf3856ad364e35" />
    <bindingRedirect oldVersion="1.0.0.0-2.0.0.0" newVersion="2.0.0.0" />
  </dependentAssembly>

Referência: https://our.umbraco.org/forum/developers/razor/48827-Umbraco-4711-and-MVC-4