I'm not sure if this is the right place to ask, but if it's not, please point me in the right direction. It seems that my top level domain is being spoofed by spammers. This is resulting in lowering my ranking in Senderbase to the point where Cisco gear kicks out all emails from my server. I have 2 domains (websites) on the server, cocoanet.us and dantesinfernophotography.com. The server's name is inferno.cocoanet.us. Checking Senderbase with mail.cocoanet.us or mail.dantesinfernophotography.com are fine, but when I check inferno.cocoanet.us its reputation is bad. It seems that the spoofers are using the IP of inferno.cocoanet.us So, what is the best way, if any, to stop the spoofing? I've already setup SPF (I know that isn't very good with spoofing, but it might catch a couple). What about DKIM??? What methods are people using these days?