On 07/24/2018 05:36 AM, Mike McCarthy, W1NR wrote: > Your IP address is flagged as spam in Real Time Block Lists. Are you > using a dynamic IP address? You may have a mis-configured server that is > allowing spammers to relay through your server. Another possibility is > your system is compromised with a spambot. > > Mike > Happens frequently to me and I'm no open relay. CentOS uses spamhaus and spamhaus blocks entire subnets if someone on the subnet spams. So unless you can afford your own subnet or pay to be on a whitelist, blacklists are a common thing for the little guy. So much for net neutrality.