...it's really funny now, absolutely no firewall now, clean install, tried with explorer, chrome, firefox, changed port, no way 
always the same page: 
 
""" 
Internet Explorer cannot display the webpage  
Most likely causes: 
You are not connected to the Internet.  
The website is encountering problems.  
There might be a typing error in the address.  
 """ 
 
What can it be? Apex setting are ok, web server enable ok, port 12345... it's really strange. :(