Forum Problem

Hello Everybody. I have a big problem on my forum which is run on the same script like yours. Every time when I woke up and turn on my computer I see that there is a lot of links to strange domains with nothing on them but usually redirecting to bad sites ;-( This links looks like :

<links removed>

Does anyone know how to block this links on my forum ?
Maciej Pienkala

Ok, I'm gonna give you the benefit of the doubt, I approved the post after removing the links and moving it to the proper section.

I know there are a couple of hacks on vb.org that can help you with spam bots. The two I've used are these:

Enhanced Captcha Image Verification - stop bots from signing up!! (http://www.vbulletin.org/forum/showthread.php?t=132482)

Hack to Prevent Spam (http://www.vbulletin-faq.com/forum/showthread.php?t=5215)