HTTP Error 500.22 - Internal Server Error (An ASP.NET setting has been detected that does not apply in Integrated managed pipeline mode.)

The issue is caused by the pipeline mode in your Application Pool setting that your website is set to.
There are two types of solutions exists,
i/ Change the Application mode to classic in IIS.
ii/ In Web.Config file add this code,
    <configuration>
      <system.webServer>
         <validation validateIntegratedModeConfiguration="false"/>
      </system.webServer>
   </configuration>