macbook pro no internet but full wifi signal

Hello people,

I got a problem with my macbook pro early 2011.

It wont load internet pages or mail. since we have a new router this problem occurs.

I got full wifi signil ( 3 stripes ) but internet isn't working.

already posted this question on : onemorething.nl but we tried very much but nothin helped.

for the post look this link : http://www.onemorething.nl/community/topic/macbook-thuis-geen-internet-wel-berei k-en-verbinding

All the other computers work just fine in the house and even my ipad en iphone work well on the network.

to specify:

Internet browsers wont load or work. ( mozilla, safari, chrome )

Mail isnt working

If I put my macbook out for a day or so and i start it up again i got internet for half a minute and then it stops.

On my guest account ( safari only account ) internet works just how it should. on the same network.

some times utorrent works while the rest isnt working and sometimes ''dropbox'' is synct when the internet isnt working.

So i think it should be something with the software. But i already 2x comco updated en 2x re-installed lion ( not a clean instal ).

also tried in ''terminal'' traceroute www.google.com what happens then is that he says: unkown hostname.

also tried to delete these files and restart my mac:

NetworkInterfaces.plist
com.apple.airport.preferences.plist
com.apple.network.identification.plist
preferences.plist

but it hadn't have any effect.

also resetted the router ( cisco EPC3925 ) but no succes.

also called UPC ( internet provider ) but they said it's a problem of apple so i should call them.

Apple was more willing to help en let me do some reset commands before starting the computer. But this had no effect.

And then the advised me to call UPC...

I also triend with a ethernet cabel but that isnt working either. It has connection and shows 'green' in network prefferences but wont do internet.

Assistent of network prefferences first always says: green green green green and then internet: red and server: red.

then i walk trought the steps and then they al become green and he says: network seems to be working fine.

But then still internet doenst work.

Does anybody know a solution ? I really dont know what to do anymore.

Thanks in advance and sorry for my bad english