The Nigerian scammers are in most of the major internet forums and because they're in a different time zone, they sign up during our night time hours and I / we catch them in the morning when we check in. I do everything i can with the tools i have to block them from returning and we're doing okay but a few will still get through initially. We have been able to block messaging until the new "member" makes at least 5 other posts on the forum. All i can do is to remind members that their antennae needs to be working whenever they get an unsolicited message from someone they dont know.