I have a club website, with a message board, and have been suffering with this for over a month. A cabinet company in England has been spamming my site with ads for their cabinets and I have been unable to stop them. They create a new user name for each post and have a rotation IP address. Initially I simply banned the IP of each post, but they must be using some sort of a proxy server to give them, seemingly, unlimited IP addresses. I have banned over 30 addresses, but they continue to come up with totally different ones that make banning a range impossible. It's frustrating.