The model backing my context has changed - c#-4.0

Question

I have a class library project where my POCO classes live along with a Dbcontext. I am using Code First with data migrations and everything has gone great up to this point. I use the class library in a console application test project and it still works fine there, but I am also trying to use the same exact class library in an MVC project and I get a "The model backing the context has changed since the database was created". Whenever I make a change to the model, I do the database migration update and everything goes well. The model has not still works in the console application just fine.
I have this method in a controller where I am trying to access the context:
public MultiSelectList GetListOfPossibleDispositions()
{
List<DALDevices3.Dispositions> dispositions = new List<Dispositions>();
dispositions = context.Dispositions.GroupBy(d=>d.Description).Select(grp=>grp.First()).ToList();
dispositions.OrderBy(d=>d.Description);
selectListDispositions = new MultiSelectList(dispositions, "id", "Description");
context.Dispose();
return selectListDispositions;
}
Any thought on what might be causing this issue or a possible work around ?
Thanks

Answer 1

In my MVC application I had a connection string name like this:
<add name="DALDevices3.DeviceContextConnectionString" connectionString="Data Source=....
so I removed the connection string since it is code first and still received the same error. I put the connection string back like this:
<add name="DALDevices3.DeviceContext" connectionString="Data Source=....
and the application works. So a connection string is not required in the DAL application, but is needed in the consuming application.