title: Implementing DI using Unity (design time configuration) in Web API 2
body: <p>I am working on implementing DI using Unity in Web API Layer. Following is the error message I am getting while calling the Service - </p>
  
  <blockquote>
    <p>Resolution of the dependency failed, type =
    "API.Controllers.LeadController", name = "(none)".</p>
    
    <p>Exception occurred while: while resolving.</p>
    
    <p>Exception is: InvalidOperationException - The current type,
    Business.ILeadManager, is an interface and cannot be constructed. Are
    you missing a type mapping?</p>
    
    <hr>
    
    <p>At the time of the exception, the container was:</p>
    
    <p>Resolving API.Controllers.LeadController,(none)</p>
    
    <p>Resolving parameter "leadManager" of constructor
    API.Controllers.LeadController(Business.ILeadManager leadManager)</p>
    
    <p>Resolving Business.ILeadManager,(none)</p>
  </blockquote>
  
  <p>Any suggestions, what is wrong ?</p>