WordPress, Installatron or Host issue ?

I did installed a few WordPress sites on some free hosting services that worked ok but now I get a paid hosting account I already encountered the first annoying issue with it and don’t know how to fix this.
So the hosting company is using a cPanel with Installatron from which you can install WordPress. I have installed WordPress with it whether in a subdirectory like /wordpress or in the main folder but the issue I encountered is that I can’t make the main http://www.example.com domain to display the WordPress site, instead it displays a “site under construction” message. The WordPress site is being displayed only if I install it on a subdirectory like /wordpress and access it at http://www.example.com/wordpress. But I want to acces the WordPress site via http://www.example.com instead.
In the main folder there are 3 files:
.htaccess
index.html – (this one displays the “site under construction” message)
.wysiwygPro_preview

What could be the problem with this and how to fix it ?