Content Advisor in Internet Explorer is a per-machine setting.
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NOTE: Content Advisor settings apply to all users on the local computer and cannot be changed by users who are not administrators on the local computer (Windows NT 4.0 and Windows 2000 only). You cannot create different Content Advisor settings for different users on the same computer. If you did not enable Content Advisor and share a computer with multiple users, contact the other users to see if they enabled Content Advisor.