WCF service authenticating problem

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Hello all,

I have problem with WCF service authenticating. Please, take a look at the
following code:

ProductsService Client proxy = new
ProductsService Client("NetTcpB inding_IProduct sService");
proxy.ClientCre dentials.Window s.ClientCredent ial.Domain = "DAGREGI";
proxy.ClientCre dentials.Window s.ClientCredent ial.UserName = "Bert";
proxy.ClientCre dentials.Window s.ClientCredent ial.Password = "Pa$$w0rd";

ProductsService Client is a ServiceContract . If I comment out three lines
with credential info, everything is fine. In other case I received following
exception:

SOAP security negotiation with 'net.tcp://localhost:8083/TcpProductsServ ice'
for target 'net.tcp://localhost:8083/TcpProductsServ ice' failed.
See inner exception for more details.

Inner exception:
System.ServiceM odel
The message or signature supplied for verification has been altered

Example is taken directly from WCF Step By Step book, and it should be
working.
I have no idea what is wrong. If you need some more information, please let
me know.

Thanks!

--
Gregi