How to ban a 'spammer'
 

I have a banned member who is constantly re-registering on a daily basis just to annoy other people.

The AE detector doesn't recognize him.
Everytime he logs in he has a different IP which means I can't block the IP address. Furthermore he uses different email addresses.

What I can do to stop him re-registering?

The only constant factor (I know of) is his ISP so the end of the host name is the same. But I can't block the ISP as it would block all users using that ISP.

Is there a way that new registrations who are using a certain ISP need to be moderated manually before their registration is completed (with 30 to 40 registrations per day it is no option to moderate all new users)? Or is there another option?

Hans

I think better way is for you to contact your host and ask them to ban all free proxies , your host will charge some $ for this but with this option users can not enter with a proxy at your forum .

2nd option .. you can use any mod from to do this but with mod you cant stop all proxies .