I would only ban the members if they where spamming the new forum; may this be via PT or normal topics.

Best bet is to be sure you list a warning publicly displaying your wishes (well, the ADMIN of your forum should do this) then if it persists ban them for violating a url policy (which would be defined in your warning).

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
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