I moved my Database First DataModel to a different project midway through development. Poor planning (or lack there of) on my part.
Initially I had a solution with one project. Then I added another project to the solution and recreated my Database First DataModel from the Sql Server Dataase.
To fix the problem - MetadataException when using Entity Framework Entity Connection. I copied my the ConnectionString from the new Project Web.Config to the original project Web.Config. However, this occurred after I updated my all the references in the original project to new DataModel project.
