IIS8 HTTP Error 500.19 – Internal Server Error

If you are running Windows Server 2012 with IIS8 and you got this error HTTP Error 500.19 – Internal Server Error. If you web.config file contains “handler” or “modules” tag.

In order to fix this, launch cmd or powershell and execute these 2 commands inside of C:\Windows\System32\InetSrv

PS C:\Windows\System32\InetSrv>.\appcmd.exe unlock config -section:system.webServer/handlers

PS C:\Windows\System32\InetSrv> .\appcmd unlock config -section:system.webServer/modules

This will unlock the handlers and modules section.