I don't know which forum software you have but go to the website of developers. Most have a database of modifications you can install..

I would recommend installing a better captcha, perhaps a humanizer, and even a mod to prevent people from posting links or images until they have x number of posts. I know there is a mod for vb that will place a post in a moderation queue if it contains a word you specify so you can read through the post before it appears on the site.

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