[Plugin: Better WP Security] 404 page error – accessing 'website'/?author=1

I’m getting email notifications that a user is trying to access a web page on my web site… /?author=1.

Is the notification coming from Better WP Security? Is this some hacker attempting to gain access? I can’t find anything in any of the settings that would clue me into the source. Anyone have any info that will help me?

http://wordpress.org/extend/plugins/better-wp-security/