ValueError: Related model u'app.model' cannot be resolved

Question

I have two applications (ook and eek say) and I want to use a foreign key to a model in ook from a model in eek. Both are

Answer 1

I encountered this error when trying to use a child model of a base model as a foreign key. It makes sense that it didn't work because there's not an id field on the child model. My fix was to use the parent on the key. Unfortunately this was not immediately intuitive and set me back a couple hours.