Posted by & filed under IDE.

Most times you see this message it means you need to upgrade your existing data or delete any existing data and start over. See this post for more info on that issue.

You will also see this message if if you have multiple configurations in your core data model in Xcode and you forget to add an entity to it’s proper configuration. You can add data to the entity but when core data tries to save the data you will see this error message.