Vista - Could not find schema information

Hi everybody,

I am developing simple applications by WCF of December CTP. I compile the
application and I don't receive error messages. Then I start but I view on
browser:

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The web.config shows a lot of messages:
Message 1 Could not find schema information for the element
'http://schemas.microsoft.com/.NetConfiguration/v2.0:configuration'.
F:\Application\Windows Communication Foundation\Example2\Web.config 3 2
F:\...\Example2\
Message 2 Could not find schema information for the element
'http://schemas.microsoft.com/.NetConfiguration/v2.0:system.serviceModel'.
F:\Application\Windows Communication Foundation\Example2\Web.config 4 4
F:\...\Example2\

and so on.

What is the problem? I have the same problem with the default application
Hello World.

Thanks in advance,
Luca Tarrini