I spent two days trying to trace why the plugin I am writing did not work. Eventually I realized that the files defining the models were not loaded at all. After several hours trying to figure this out I came across this explanation provided by zuha-3:

My bet is that you don’t have a plugin defined somewhere. I had the same problem in a couple of places after the upgrade because I had forgotten to name which plugin the model could be found in.


belongsTo = array(
className = [PLUGIN].[MODEL]

instead of...

belongsTo = array(
className = [MODEL]


And this goes for all relationships, and you might have just missed one.

And so finally it worked. This should be like written in really large letters on the page that talks about plugins in CakePHP documentation. Two days for this simple stupid thing…