You can independently enable this via web.config. Add the following line to within of the system.webserver tag:
​

<httpErrors errorMode="Detailed"/>

If the web.config file does not exist, you must create it.

Newly created configuration file example:

<?xml version="1.0" encoding="UTF-8"?>

<configuration>

<system.webServer>

<httpErrors errorMode="Detailed"/>

</system.webServer>

</configuration>

​

Note: If the option is enabled, no own HTTP error messages can be defined more.
This function can only under Windows / IIS be used.