You should have an entry in your config file that looks something like this:
<add name="MyEntity" connectionString="metadata=res://*/DataAccess.EntityFramework.MyEntities.csdl|res://*/DataAccess.EntityFramework.CodeStashEntities.ssdl|res://*/DataAccess.EntityFramework.CodeStashEntities.msl;provider=System.Data.SqlClient;provider connection string="data source=MyDataSource\SQLExpress;initial catalog=MyCatalog;Integrated Security=SSPI;multipleactiveresultsets=True;App=EntityFramework"" providerName="System.Data.EntityClient" />
Your entity framework connection in your code should use the name supplied at the start.