Thankfully there is a relatively easy solution available, and it has proved to be 100% effective for those which have now implemented it: simply add the vBulletin Question and Answer Verification option into the registration process. This requires human thinking to be able to complete a registration, by asking a question such as “what colour was the white cloud?” or “what is the fourth word in this sentence?” for example.
Read more: vBulletin forums hit by reCAPTCHA cracking spam bot | PC Pro blog http://www.pcpro.co.uk/blogs/2011/01/12 ... z1B0yi60fY
Full article on vBulletin forums hit by reCAPTCHA cracking spam bot vBulletin forums hit by reCAPTCHA cracking spam bot | PC Pro
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