Open http://localhost/ in a web browser. If you see something like in the previous screen, then the Apache installation is working properly.
If you have Windows Firewall enabled (check it in Start Control Panel Network and Internet Connections Change Windows Firewall settings), the first time you access to the Apache welcome page, it will appear the screen shown in Figure 1. Select Unblock on the Windows Security Alert. For other firewalls, make sure port 80 is open.