Effectively Banning Users?
 

Unfortunately we have a member who has been banned literally dozens of times. I've banned his email addresses, I've banned his IP addresses, yet he still manages to sign up again with a new email address and IP. How does he manage to circumvent our forum? Is there nothing I can do to be rid of this annoying troll? The time it takes trying to rid ourselves of this loser is giving me second thoughts about bothering with a forum at all.