Amazon Workmail unable to send to Mimecast recipients

Question

How do we get in touch with support without a support plan to raise an issue with bounced emails to a variety of email addresses all using Mimecast spam protection.

All emails are being bounced back sent to multiple customers.  Configuration is fine and has been working for years but after todays issues and the lack of support available I think these clients will soon be moved to Microsoft365.

Please help and provide some method to get in touch when IP addresses need to be cycled.

re:Post Agent · Answer

I apologize for the frustration you're experiencing with Amazon WorkMail and the bounced emails to Mimecast recipients. Unfortunately, without a support plan, direct contact with AWS support for this specific issue is limited. However, there are a few steps you can take to troubleshoot and potentially resolve the problem:

1. First, check your WorkMail and Amazon SES (Simple Email Service) configurations. Ensure that your domain and email addresses are properly verified in SES, and that your DNS settings, including SPF and DKIM records, are correct.

2. Review your MX records to make sure they are correctly pointing to WorkMail and that there are no conflicting entries.

3. Check if your sending IP address has been blacklisted. You can use various online tools to check IP reputation.

4. Enable message tracking in Amazon WorkMail and review the logs for any specific delivery problems or error messages.

5. If the issue persists, you may need to contact Mimecast support, as the problem could be on their end with how they're handling incoming emails from AWS IP addresses.

For getting support without a plan, you have a few options:

1. Post your question on AWS re:Post (formerly AWS Forums), where AWS community members and occasionally AWS employees provide assistance.

2. Check the AWS Status page to see if there are any known issues with WorkMail or SES in your region.

3. If you believe this is a widespread issue affecting multiple customers, you can try reaching out to AWS on social media platforms like Twitter (@AWSSupport) to bring attention to the problem.

4. Consider upgrading to a support plan, even temporarily, to get direct assistance with this critical issue.

Regarding cycling IP addresses, this is typically handled automatically by AWS. However, if you believe this is necessary, without a support plan, your best option is to post on AWS re:Post explaining the situation in detail and requesting guidance.

If the issue continues and you're considering moving to Microsoft 365, it might be worth evaluating the costs and benefits of an AWS support plan versus migration costs and potential downtime.  
**Sources**  
[Mail routing - Amazon WorkMail](https://docs.aws.amazon.com/workmail/latest/adminguide/mail-routing.html)  
[Workmail not receiving mail | AWS re:Post](https://repost.aws/questions/QUWQPuy722RfODHKbCDCqDSg/workmail-not-receiving-mail)  
[Amazon WorkMail You have exceeded the sending limit for this account. | AWS re:Post](https://repost.aws/questions/QUhEJVl4M_Qhq49tam0sRD7A/amazon-workmail-you-have-exceeded-the-sending-limit-for-this-account)

Amazon Workmail unable to send to Mimecast recipients

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