Did you encountered following exception / error when trying to run ASP.NET MVC web application?

The view must derive from WebViewPage, or WebViewPage

View must derive from WebViewPage error

or

Type 'ASP.PageViews_ViewStartcshtml' does not inherit from 'System.Web.WebPages.StartPage'.

ViewStart does not inherit from System.Web.WebPages.StartPage

I encountered while I was playing with MVC 5 (applies to MVC 3 and 4 also) application.

Every razor page should inherit from System.Web.Mvc.WebViewPage. You can resolve this issue by adding following line at the top in each view razor (*.cshtml) page:

@inherits System.Web.Mvc.WebViewPage

and add following line at the top of _ViewStart.cshtml :

@inherits System.Web.Mvc.ViewStartPage

or you can add a web.config file and add following (in root of Views folder where the Razor pages reside)

<?xml version="1.0"?>

<configuration>  
  <configSections>
    <sectionGroup name="system.web.webPages.razor" type="System.Web.WebPages.Razor.Configuration.RazorWebSectionGroup, System.Web.WebPages.Razor, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35">
      <section name="host" type="System.Web.WebPages.Razor.Configuration.HostSection, System.Web.WebPages.Razor, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" />
      <section name="pages" type="System.Web.WebPages.Razor.Configuration.RazorPagesSection, System.Web.WebPages.Razor, Version=3.0.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" requirePermission="false" />
    </sectionGroup>
  </configSections>

  <system.web.webPages.razor>
    <host factoryType="System.Web.Mvc.MvcWebRazorHostFactory, System.Web.Mvc, Version=5.2.2.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" />
    <pages pageBaseType="System.Web.Mvc.WebViewPage">
      <namespaces>
        <add namespace="System.Web.Mvc" />
        <add namespace="System.Web.Mvc.Ajax" />
        <add namespace="System.Web.Mvc.Html" />
        <add namespace="System.Web.Routing" />
      </namespaces>
    </pages>
  </system.web.webPages.razor>

  <appSettings>
    <add key="webpages:Enabled" value="false" />
  </appSettings>

  <system.webServer>
    <handlers>
      <remove name="BlockViewHandler"/>
      <add name="BlockViewHandler" path="*" verb="*" preCondition="integratedMode" type="System.Web.HttpNotFoundHandler" />
    </handlers>
  </system.webServer>
</configuration>  

In MVC application there are two web.config files, one in the root of the main application and other in root of Views folder where the Razor pages reside.

Happy Coding !!