You've solved your own problem. But just for the sake of telling a story, the context in which I usually see 'Logical end of file reached' error in Logic 7 is in the audio editor.
If you have a piece of audio, highlight a blob in the middle, cut it with the delete key so that Logic removes a bunch of samples, and then go to perform further deletion edits, you may start to get this message each time you perform one. It doesn't actually cause anything to go wrong with the edits, but it does annoy you. (until you re-open the session or something.)