IMail does not send out backscatter by design. To make sure that IMail is not sending out Backscatter, make sure that NONE of your Spam checks are set to Bounce. Setting to Bounce does not ‘get back’ at the spammers as a lot of users think. This in itself makes you or your server a ‘spammer’ due to the fact that over 90% of spam sent is done with spoofed addresses, and your bounce will be returned to a valid user that did not send the spam in the first place. Change you action on spam to be something other than bounce. Also make sure no Domain level or user level rules are set to Bounce any spam messages. If neither of these scenarios apply, you may, instead, be getting listed for what is known as Sender Callouts.
You will want to check your AntiSpam settings. In the Admin go to the Connection Checks settings, and make sure you are NOT doing ‘Verify MAIL FROM Address’ checks. If this option is checked, uncheck it and save the changes. Then stop and restart the SMTP and the Queue Manager services.
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