Crash - Dog has no NSEntityDescription

Running the Dog Walk app first time and crashing with:
*** Terminating app due to uncaught exception ‘NSInvalidArgumentException’, reason: ‘An NSManagedObject of class ‘Dog’ must have a valid NSEntityDescription.’

Stuck. Any ideas?

Double-check your data model to make sure all the identifiers match up with the manual. You could also trace through your CoreDataStack class to make sure all the components of the stack are being initialized ok.

Have fun!

I checked everything, but no luck. So, I reworked the project from a fresh copy of the Chapter 3 project. It worked, but I noticed a curious thing, which may or may not have anything to do with my problem. As I went to create/save the model, the project file already contained the “Dog Walk.xcdatamodeld” file. I decided to abort the save, delete the file in Finder, then proceed. It worked.