I am trying to figure it out how to set configurations on my service and Silverlight client App to work on Secure Windows Authentication. I have my service configured like this: <binding name="currentCustomBinding"> <binaryMessageEncoding /> <httpsTransport authenticationScheme="Ntlm" bypassProxyOnLocal="true" /> </binding> </customBinding> <serviceMetadata httpGetEnabled="False" httpsGetEnabled="True" /> <serviceDebug includeExceptionDetailInFaults="false" /> </behavior> <service name=" OperationService" behaviorConfiguration=" OperationServiceBehavior"> <endpoint address="" behaviorConfiguration=" OperationServiceBehavior" binding="customBinding" bindingConfiguration="currentCustomBinding" contract="OperationService" /> </service> Any ideas? 10q