Can't access some websites

[WhiteSlash28]

Hi guys, I really need some help.

I have a weird problem actually.

Let me explain this to you :
I have a shared internet connexion (wifirst, for all people in my flat). But I can't connect 2 computers on it with the same account. So instead of paying 2 accounts, I use connectify. I have 3 computers (my main, my laptop and my gf's).

I run connectify on windows seven 64x. (my main computer)
I can connect the laptops (windows seven) on it and use the internet normally.
BUT
I when I connect the laptops on linux (dual boot, ubuntu 12.04), I can't use the internet normally. I mean, a lot of websites are unreachable (facebook, hotmail...)... and this is very slow.

How to do with that ? Any help ?

Thank you for reading.

[elliotbeken]

Can you ping the websites you are trying to access:

Open a terminal:

ping google.com

or

ping hotmail.com

[WhiteSlash28]

Yes, I can ping facebook, and google and hotmail !
(I even tried to do a wget on facebook and it worked)
But with firefox or chrome, I can't go to any of these websites !