WCF - SvcTraceViewer: "The body of the message cannot be read because it is empty."

hello

I have a service that do this:
    public bool AuthenticateUser(string strUserName, int nPasswordHash)

It's called from ASP.NET login page. Executed the code with debugger running on Visual Studio and NO exception reported/detected. However when I view with "SvcTraceViewer", I keep seeing:

   "The body of the message cannot be read because it is empty."

Here's web.config of web service exposing authentication service:


... more ...
    
        
       logMessagesAtServiceLevel="true" logMessagesAtTransportLevel="true" />
 
 
  
    
                 binding="basicHttpBinding"
        bindingConfiguration=""
        name="Basic"
        contract="xxxxx.SecurityServiceLib.ISecurityService">
        
        
            binding="mexHttpBinding"
        name="MEX"
        contract="IMetadataExchange" />
        
   
    
                
    
    
   
  
 
        
  
   
    
    
   
  
 
    
... more ...


Any idea? I been banging my head against the wall because of this for sometime and still bit stuck.

dev