Looks as if you've been randomly chosen to experience a hassle. If you haven't changed any of the security settings within your browser, it''s likely a cookie conflict. Try deliberately logging out. If that doesn't work, delete all your cookies.
Now, "delete all your cookies" is a cop out on my end. You can find specific cookies and delete them but it's usually more trouble than it's worth. I'm searching right now for the Benchrest Central cookie template and when/if I find it I'll offer something to search for - should you have a reason not to delete all your cookies.