[Unable to install Revive Adserver]

@Erik Geurts as per the link you provided I have completed the first three steps. I am stuck at the fourth step, (start installation). 

 

[Unable to install Revive Adserver]

@Erik Geurts Are the instructions given in the link for CentOS 7 ?

 

[Unable to install Revive Adserver]

I have installed CentOS 7 in virtual box. 

Then I installed Apache Version 

apache version: 2.4.6, php version 7.0.8, mysql  version 5.6.31. (Basically I have finished installing LAMP.) 

I have satisfied all the technical requirements for installing revive ad-server.(https://www.revive-adserver.com/support/requirements/)

Then I followed the steps to install revive ad server in the follwing link : http://linoxide.com/linux-how-to/install-revive-adserver-ubuntu-15-04-centos-7/

But as I follow the second link, I Created new Database, Downloaded Revive Adserver Package (version 3.2.2)., Configured Apache Web Server, Fixed Permissions and Ownership, allowed firewall programs to allow port 80 (http). 

BUT in the last step of web installation, The web server simply says, "server not found".

My  network is connected, my network settings says "proxy -none".

I really need help. Thanks!!