My client is ISP1. I submit mail to the postfix server for my domain (server running on ISP2). I use relayhost=smtp.ISP2
> <<< 554 Service unavailable; Client host [smtp.ISP2] blocked using Barracuda > Reputation; http://www.barracudanetworks.com/reputation/?r=1&ip=IP.of.my.doman > 554 5.0.0 Service unavailable Is there a way to make relayhost work in this case?
