Looks to be plugin related. Do you have a wrapper plugin and are attempting to wrap a component/module that is not set for public usage?
At any rate here is the language lines you're looking for, but I advise against editing them out:
[code:1]\language[/code:1]
Line: 27 and 28
[code:1]
DEFINE('_NOT_AUTH','You are not authorised to view this resource.');
DEFINE('_DO_LOGIN','You need to login.');
[/code:1]