Make sure no other program conflict Wamp such as IIS, Skype, ZoneAlarm, Firewall/Antivirus, NOD32, Eset, any web related programs, browser add-ons ...
IIS (Internet Information Services ) and Apache/Wamp are both web server and might conflict in some way, so you have to disable IIS in order for Wamp to work
Disable IIS in Vista/W7:
Control Panel, Uninstall Programs, Turn Widows Features On or Off, uncheck Internet Information Services
Disable IIS in XP:
Control Panel, Add/Remove Programs, Add/Remove Windows Components, uncheck Internet Information Services (IIS)
Restart computer, then restart Wamp
Also, in folder C:\WINDOWS\System32\drivers\etc, open file hosts and delete anything in this file and have only this line below and nothing else
127.0.0.1 localhost
If using Skype, open Skype > Tools > Options > Advanced > Connection uncheck "use port 80..." restart Wamp then Skype
Have fun,
FREE One A DayFREE PhotoFREE GamesFREE WebsitesFREE Portable GPSFREE WAMP Guides