I have a Macbook with OS X 10.6.8. Yesterday it was working just fine, but not today when I open it up.
It gets the right IP, subnet, Gateway and DNS server from my router. I am able to ping any domain e.g. www.google.com with terminal and it works just fine, so DNS is working properly. I even checked that DNS server is my routers address, which is correct. However I am not able to browse the internet with Safari nor Firefox. I tried to disable the firewall, no help. Currently it's enabled and browsers are permitted.
Our PC and tablets work without any issues, which means that the problem is isolated to the Macbook.