Safari cannot connect to Server - a tricky question for someone smart

Safari says that it cannot connect to the server. That is when I type in a website I get that message for the corresponding server. Spotify, email, Firefox and all other programs do not connect either. Network diagnostics says that the internet connection is working properly. All other computers in the house connect normally. A ping test works normally. A traceroute does not. I have access to the router by typing in the IP address. We are on Wifi. I have done the following

- restarted router and computer, manytimes!

- uninstalled little snitch

- deleted and the renewed the wifi connection

- deleted all cookies

- reset PRam

- renewed the DHCP lease

- have run disc utilities and repaired permissions

- made sure none of the proxy boxes are checked except for use passive ftp

I am using a Macbook Pro 17" i5 on 10.7.5. The problem started when the computer did not shut down properly last nite.

I have exhausted all my known fixes, any ideas? Thanks, John