Internal Server Error 500.24

I fixed the error by changing following files:

vwd.webinfo (added useClassicPipelineMode tag):

<?xml version="1.0"?>
<!-- 
  Visual Studio global web project settings.
-->
<VisualWebDeveloper>

  <iisExpressSettings windowsAuthentication="enabled" anonymousAuthentication="enabled" useClassicPipelineMode="true"/>
</VisualWebDeveloper>

Web.config:

<system.webServer>
    <validation validateIntegratedModeConfiguration="false"/>
</system.webServer>

In Visual Studio, select your web project in the solution explorer, then open the properties window (keyboard shortcut F4)

You should be seeing a list of properties to configure your IIS Express Server.

Change the option "Managed Pipeline Mode" from Integrated to Classic