'NoneType' object has no attribute '_meta'
The solution is to first list all app_labels for contenttypes, and then delete any not in use.
In : from django.contrib.contenttypes.models import ContentType In : for ct in ContentType.objects.all(): print ct.app_label ....: picasaweb lifestream readernaut delicious mapfeed comments ...
I could then delete the unused contenttypes.
ct_list = ["delicious", "flickr", "photologue", "twitter"] for ct_label in ct_list: for ct in ContentType.objects.filter(app_label=ct_label): ct.delete()
And no more errors! For more details take a look at David's article.