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I have spent a whole day wondering why authenticated users could create, but not edit their own content. I discoverd this at the point that I had Domain Access and Organi Groups and a bunch of custom code enabled, so took quite some hairpulling, disabling modules one by one, to discover that Entity translation was the cause. The setting 'edit original values' to be specific. Of course this is a big *duh* but maybe I'm not the only one here. The effect of this setting might be give a more prominent place in the documentation or project place.