There are a bunch of ways to do this..
Turn off anonymous posting rights. (Lots of posts on how to do this)
Turn on Captcha (have to enter a
string displayed as an image) for registration:
Turn on Captcha for posting.
Here are the common captcha config settings you can add to your jforum-custom.conf file.
captcha.registration = false
captcha.posts = false
captcha.ignore.case = false
[originally posted on jforum.net by monroe]
