Backscatter is a problem that arises when an email server receives bounced messages that come from remote site to a non-local recipient. In simple terms non-delivery reports or delivery status notifications are sent to a mail server that never originated the emails. Backscatter can be a big IT administrative headache, if it's not fixed it can bring down a server and spammers can use this to create a DoS style attack. Best way to prevent Backscatter to prevent bounces generated to non-local recipients, the bounces should be rejected during SMTP session. Mike at Message Partners emailed me about his recent experience with Backscatter and read his recent post at his blog. For more information please visit Backscatter FAQ at Spamlinks. If you've got ideas, suggestions, questions or other ways to control spam please let me know, by leaving a comment here. Posted by: Jayaprakash Kannoth    Source