SpamCop FAQ : Help for abuse-desks and administrators :
SpamCop does not ordinarily bother relay admins. It must have gotten 'stuck' on your hop in the chain. Perhaps one of these possibilities explains the problem:

Your server's received line didn't indicate an incoming IP address.

Even if your server is performing reverse lookups on the senders to verify that they provide the correct hostname on HELO, SpamCop has no way to know that this check has been performed unless the IP address of the sender is actually included as part of the received line. Either upgrade your SMTP server or change the settings so that the source IP address of the sender is identified. Hopefully, you will also disable third-party relay completely, but that is your choice.

More information on "relay rape":

"Relay rape" is a term used to describe the unwanted use of your open (trusting) email systems by spammers. There is another antispam organization, the Mail Abuse Prevention System (MAPS), that has a lot of information on this subject. Please visit the web site:

https://ers.trendmicro.com/

This page explains why you should stop spammers and how to do it.

The email was received at your site BY a server in one domain and then it left your organization through a server that claimed to be in different domain.

This is the hardest problem to solve. It's perfectly legal for an email to be received "by" smtp1.ge.com and then in the very next line be received "from" mailserver.gecapital.com. Hopefully, you can find an internal solution to this problem, because it does cause confusion for SpamCop (and just general confusion), particularly when the IPs involved don't have name service or are part of a private network (intranet). This type of problem usually affects the SpamCop user, not the recipient of the complaint. This problem can also occur with some forwarding services such as bigfoot and iname - although those two examples have already been 'fixed' by explicit exceptions to this rule in SpamCop's code.

SpamCop was unable to parse the received line your server inserted even though the line did include an IP address.

This is very rare, but it may be a bona-fide bug in SpamCop.

For help with any of these problems, please post a message in the forum or see the FAQ "How to contact a real person".
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