AWS WorkMail Synacor Abuse Report

Hi! Thank you for your question.

In short - If you do not see an issue on your SES dashboard (no complaints/bounces, etc) from the AWS-side you should be in good shape, but please do review the below mentioned documentation at your convenience to ensure you have everything setup properly.

It can be difficult to interpret what is going on with abuse reports, bounces, etcetera especially when the messages are internal to your organization and opt-in as you have indicated. AWS Workmail uses SES to send email, so for the remainder of this message I will be focusing on SES.

This particular complaint is coming from a FBL (Feedback Loop) provider 'Synacor' coming back through SES as a notification. Synacor is one of many FBLs that house databases for complaints of Spam/Junk email. Additional information can be found here https://docs.aws.amazon.com/ses/latest/dg/faqs-enforcement.html (scroll down to Amazon SES complaints through feedback loops FAQ)

Also note that you can view reputation/bounce issues via your SES console (https://console.aws.amazon.com/ses) and/or via CloudWatch (https://docs.aws.amazon.com/ses/latest/dg/event-publishing-retrieving-cloudwatch.html)

You can also set up notifications for SES (which it appears you already have). This is good information to review and confirm you have everything following best practices: https://docs.aws.amazon.com/ses/latest/dg/monitor-sending-activity-using-notifications.html#monitor-sending-activity-using-notifications-considerations

You may have Account-level suppression lists turned on - you can check by following the guide here: https://docs.aws.amazon.com/ses/latest/dg/sending-email-suppression-list.html
If you have that turned on and received a 'complaint' - SES doesn't count the messages that you send to addresses on your account-level suppression list toward the bounce or complaint rates for your account. This could be why you do not show any up tick in complaints if the recipient is added to this list.

Removing the email addresses that show on the list of recipient(s) that complained is the recommended solution, but (without assuming too much about your organization) we can start by looking at the reason this may have happened.

Is it possible someone that originally opted-in reported it as spam either by accident, or no longer wanted to receive it and did not opt-out properly. Also, depending on how the users in your organization have their email client(s) setup; 3rd party spam filter add-ons could have flagged and auto-reported the message as spam causing this.

Hopefully this helps!