It's been two days that I try everything I think to solve my problem, but there I really do not see where it comes from.
On a Centos 7 server I configured Apache to listen on ports 80 and 5555. It works properly locally, but the connection is refused from any other machine on the network (the ping works correctly).
Listen 0.0.0.0:80
Listen 0.0.0.0:5555
The folder is configured to accept all connections:
Require all granted
I added the ports in SELinux and in firewalld. I even tried setenforce 0 and disable the firewall, but still the same.
In fact, the connection is refused with port 5555 while on port 80 an authentication window appears, but I do not know where it comes from.
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 300/httpd
tcp 0 0 0.0.0.0:5555 0.0.0.0:* LISTEN 300/httpd