The EntityContainer name must be unique. An EntityContainer with the name 'Entities' is already defined

Question

For a little background:

I have a DLL project with the following structure:

Rivworks.Model (project)  
  \\Negotiation (folder)  
      Model.edmx          


        

Answer 1

If you are using web deployment from Visual Studio sometimes doesn't delete the old dlls. I had the same problem, change to Web Deployment Package and didn't give me problems.