SpamCop FAQ : SpamCop Parsing and Reporting Service : Parsing and reporting spam with SpamCop - decisions, problems :
SpamCop tries to find a reporting address for the administrators of relays used in the sending of spam. Unfortunately, for various reasons, it is not always possible to find a valid, working address.

Open relays are often found in far-off countries where the software is out-of-date and cannot be upgraded because the hardware can't handle newer versions. Sometimes the server is long forgotten, stuffed in a closet, seldom looked at much less monitored.

Finding an email address in whois databases beyond ARIN can be difficult without human eyes as the information is not presented in a standard format and can be buried several layers deep. Often, even if an address is found and a report sent, language barriers prevent the intent of the message from getting through.
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