[voltron81]

Hello to everybody.
I've realized a mailserver based on ISPConfig and debian.
It's working just fine.

I've just one problem: sometimes happen that somebody try to send me an email from a ISP that is NATing the IPs; the ISPConfig spamfilter is of course checking that email and mark is as NOT spam.
So the email is passed to the receiver, that is using a local spamfilter.
Well, this spamfilter is marking that email as SPAM.

This is the scenario:

LocationA _____ LocationB ___________ LocationC
the sender_____ISPConfig server _______ receiver


Doing an mxtoolbox blacklist check, the IP of the sender(that in reality is of his ISP, because it's NATing all his customers to few IP) is blacklisted...
For the moment I just remove that IP from the blacklist and I solve the problem.
But unfortunately this problem is happening quite often.

So my question is: there is a way to setup the ISPConfig to just avoid the IP of the sender when is passing the email to the receiver, so that the spamfilter on the locationC will not mark that email as spam?

Or do you have another idea to solve this problem?

Thanks
Michele