ISPC3 Changed from Nginx to Apache after using APS Installer

Last night i was busy installing and trying packages from the APS Installer...
Now my server runs on Apache instead of Nginx... i seriously don't understand.

How can i switch back to Nginx ??
Now it says in the bottom Apache/2.2.22 (Ubuntu) Server

 

For the people who have the same problem do this ONLY if you have your server installed with NGinx and it has gone to Apache2:

dpkg -S `which apache2`
sudo apt-get purge apache2 apache2-utils apache2.2-bin apache2-common
sudo apt-get autoremove
nginx -t

 

And if you get an 403 Forbidden error:
edit /etc/nginx/nginx.conf
change user www-data to ispconfig

 

Wise lesson: never use APS.