title: System.InvalidOperationException: Mapping and metadata information could not be found for EntityType Foo.Bar
body: <p>I am at my wit's end trying to resolve this.</p>
  
  <p>I have a pretty significantly large MVC project using 4 Entity Framework models. The models are compiled into a separate assembly/class library type project.</p>
  
  <p>Until a few days ago, everything was working fine. I was on leave for 2 days and someone tweaked the model and he's called severely sick.</p>
  
  <p>When I came back today, I noticed that the app just won't start. It shows you the yellow screen of death with the following exception message:</p>
  
  <pre><code>System.InvalidOperationException: Mapping and metadata information could 
  not be found for EntityType 'MyNamespace.MyClassName'
  </code></pre>
  
  <p>I checked out a few articles (<a href="http://blogs.infosupport.com/mapping-and-metadata-information-could-not-be-found-for-entitytype-schema-klant/" rel="nofollow">http://blogs.infosupport.com/mapping-and-metadata-information-could-not-be-found-for-entitytype-schema-klant/</a>, <a href="http://matheusandcode.wordpress.com/2011/11/13/mapping-and-metadata-information-could-not-be-found-for-entitytype/" rel="nofollow">http://matheusandcode.wordpress.com/2011/11/13/mapping-and-metadata-information-could-not-be-found-for-entitytype/</a>) and questions &amp; answers from here and they all suggest that I cross-check for misspellings or missing properties between the POCO's and the model generated entities.</p>
  
  <p>I have about 400+ entities. However, I checked the entity that it throws an exception while creating the entity set of, and there are absolutely no spelling mismatches. I've spent over 5 hours on checking this and I am tired and frustrated.</p>
  
  <p>Anyone have any other leads as to the possible causes for this error?</p>
  
  <p>I've cleaned, rebuilt, checked for spelling errors, missing properties, cross-checked parity between the conceptual and storage model using the Table Mappings window, the model browser and even SQL Server Management Studio, I've taken print-outs and marked every property on paper against the one in the POCO, I've rinsed and repeated a few times, but the error just won't go.</p>
  
  <p>I am using Visual Studio 2010, EF 5, MVC 4 and the Entity Framework POCO Generator package.</p>