title: Cannot use project as a library reference
body: <p>I have a ASP.NET Web Forms Application called ProfileManager. Inside this application, I have classes with namespaces ProfileManager.Entity, ProfileManager.DAL, etc.</p>
  
  <p>I am referencing the dll of this project from another ASP.NET Web Forms Application.</p>
  
  <p>In the code of the second application, I am writing lines like this</p>
  
  <pre><code>using ProfileManager.Entity;
  using ProfileManager.DAL;
  </code></pre>
  
  <p>But Visual Studio are giving the following error for the above lines</p>
  
  <p><strong><em>The type or namespace name 'ProfileManager' could not be found (are you missing a using directive or an assembly reference?</em></strong></p>
  
  <p>I am attaching screenshots to explain.</p>
  
  <p><a href="https://i.stack.imgur.com/6Hsrv.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/6Hsrv.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/wadWY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/wadWY.png" alt="enter image description here"></a></p>
  
  <p>I changed the name of my ProfileManager project and also all the namespaces to ProfileManagerLibrary. But still I get the same error.</p>
  
  <p>How can I solve this problem?</p>