A notebook cannot send a single net package using Vista Buisness

> Hello, friends.
>
> I've got Vista Home Basic with my Toshiba U200-10K. When I tried to connect
> to the Internet, using an ADSl-modem, following trouble has appeared:
>
> The Internet connection has been established and the computer has got a
> dinamic IP, but I can't open any site. The problem is the PC cannot send a
> single net package to the network (I used "ping"), but only gets traffic. The
> Windows fire wall has been shut down and its service has been disabled. None
> anti-virus programms or other fire walls were installed. The network adapter
> (Intel PRO/100 VE Network connection) has the latest version of driver.
>
> I had installed the WindowsXP on the notebook and the problem has
> disappeared at all. Next I bought the Windows Vista Buisness, thinking
> there's a problem in a recovery Vista disc I got with the PC. I've installed
> Vista Buisness and the trouble came again. I canot get to the Internet,
> cannot register Windows, cannot get any updates. So, no doubt, that's a
> problem of Windows Vista.
>
> My service center said the Windows is not their problem. I've written to the
> Toshiba, but they can't give me any usefull advice, except "Shut down the
> fire wall" (what I tried for thousand times). I wrote to the Intel with the
> same result, namely, "such type of adapters is not our problem, ask your
> motherboard's manufacturer". I gave way to despair, I tried everything I
> could, I don't know what I can do now and what for I've spent so much money
> for that Vista.
>
> If anybody has some ideas of problem fixing, all your suggestions will be
> very much appreciated.
>
> Buy
>