I am using a WCF service running on a windows 2003-SP2 Server with IIS 6.0 inside an asp.net application.
I have another asp.net application (the client) running on the same server attempting to connect to the WCF service.
I am trying to get the client app to connect-as the user logged into the browser to the WCF service.
My error is the dreaded:
The HTTP request is unauthorized with client authentication scheme 'Negotiate'. The authentication header received from the server was 'Negotiate,NTLM'
The website in IIS has:
Annonymous Access: Disabled
Windows Authentication: Enabled
The web.config on both the server and client contain the following:


The WCF service has the following in the web.config:

 
   
     
       
         
       
     
   
 
 
 
   
     
     
     
   
 
 
   
     
       
       
       
       
       
     
   
 


The Client has the following in it's web.config:


   
     
                  openTimeout="00:01:00" receiveTimeout="00:10:00" sendTimeout="00:01:00"
          allowCookies="false" bypassProxyOnLocal="false" hostNameComparisonMode="StrongWildcard"
          maxBufferSize="65536" maxBufferPoolSize="524288" maxReceivedMessageSize="65536"
          messageEncoding="Text" textEncoding="utf-8" transferMode="Buffered"
          useDefaultWebProxy="true">
                      maxBytesPerRead="4096" maxNameTableCharCount="16384" />
         
                          realm="" />
           
         
       
     
   
   
     
       
         
           
         
       
     
   
   
      http://myserver/myapp/appService.svc"
        binding="basicHttpBinding" bindingConfiguration="BasicHttpBinding_IThirdPartyService"
        behaviorConfiguration="Delegation"
        contract="ThirdPartyService.IThirdPartyService"
        name="BasicHttpBinding_IThirdPartyService" />
   
 
Above all of the public methods in my service, I have:
_
(Yes I am unfortunately forced to write in VB.net)
Now as far as I can tell from every blog, forum, article or any other source I could find, this should work. 
Oddly enough it does work if I have the WCF service deployed in production (IIS 6) and deploy the client app
on my Dev machine which runs IIS 5 in windows XP (same msi as deployed in production, same settings in IIS). 
Anyone have any idea why this would be happening?
Thanks everyone!