Theme Editor: Sorry this file cannot be edited.

Clean install of 2.7.1. When I click on Appearance Editor I get the message, “Sorry, that file cannot be edited.” Same with the Plugins editor.

Any ideas? If it’s a permission thing, please tell me what the permissions should be for what files. I’ve played with that theory as did my host and nothing we did with CHMOD seemed to work.

Is there something else other than permissions that is causing this?