Just turn off anonymous posting / remove it / default off. Seriously.
Admin Panel -> Groups -> Permissions -> Anonymous posts
Check if "Anonymous" is in the "General" group (Admin -> Users -> Groups)
Admin Panel -> Users -> [search for Anonymous] -> Permissions and revoke all its access rights.
> While creating forum, you can choose option "Deny anonymous postings".
This should be an 'allow anonymous postings'. For two reasons. Preferences should default to sane values. Preferences should be worded positively. So either 'require users to register' or 'allow anonymous postings'. Never the negative.
This really shook me up - especially since it has been covered on the forum so many times. [originally posted on jforum.net by jforumapp]