Hallo, How can I found out why KPN (ISP in The Netherlands) is always blocking the IP of my mailserver? Is there a way to scan my server for problems or abuse programs? Or is it a user maybe who sending bad email? How can I find this out? Postfix + dovcot Thanks!
Check the mailqueue with "postqueue -p" to see if there are unusual mails in the queue. And you can check the mail.log file to see if a user sends out large amounts of email, e.g. newsletters.
Mailscanner is a spam scanner for incoming emails similar to amavis that is used on your server, so this will not help you with your problem as you run already a spam scanner and it would also break your whole setup.
