I know I have several customers that has setup email forwarders. And I am concerned that this is the reason for the listing in ips.backscatterer.org – because when there is sent spam to domains on my server that is forwarded, then that spam is forwarded from my server.
Could this be the reason? Any suggestion on what to do? Should I deactive email forwarders in DirectAdmin, is that what other does when running shared hosting servers?
I have SpamAssassin on the server, however the default setup is that it is not activated, and so that each customer themself must activate SpamAssassin if they want it.
I am not using SpamBlocker setup from user nobaloney.