Why am I seeing an increase in bounce code 60 from SES?

Summary

An increase in bounce code 60 from SES appears to have no single cause, but rather can be triggered by a variety of potential issues. These include transient server problems, rate limiting on the SES account, emails being classified as spam, authentication issues (SPF, DKIM, DMARC), recipient server configuration problems, invalid email addresses, greylisting techniques, or even a SES assigning code 60 to Out Of Office replies. The bounce code itself is a generic code and is implementation-specific, so it could vary depending on the mail server and doesn't appear to be trending in aggregate.

Key findings

  • Generic Code: Bounce code 60 is often a generic error indicating an issue, though the specific details can vary.
  • Transient Issues: Temporary problems with the recipient's server, such as being unavailable or too busy, can trigger bounce code 60.
  • Rate Limiting: Exceeding SES sending limits may result in bounce code 60.
  • Spam Classification: Recipient servers might be classifying emails as spam, even if they are not intended as such.
  • Authentication Problems: Issues with SPF, DKIM, and DMARC can lead to deliverability problems and bounce codes.
  • Server Configuration: Problems with server configuration on either the sending or receiving end can trigger the error.
  • Invalid Addresses: The bounce code can sometimes be related to invalid or non-existent email addresses.
  • Greylisting: Greylisting, a spam-fighting technique, may cause temporary rejections and an increase in bounce code 60.
  • OOf Replies: Bounce code 60 may occur from SES assigning the code to Out Of Office replies.
  • No Trending Aggregation: Bounce code 60 is not showing to be a trending issue.
  • Implementation Specific: SMTP enhanced status codes can be unique to each mail server and therefore vary.

Key considerations

  • Check SES Limits: Review SES sending limits and confirm they are not being exceeded.
  • Verify Authentication: Ensure SPF, DKIM, and DMARC records are correctly configured.
  • Monitor Reputation: Check sender reputation and ensure it remains healthy to avoid spam classification.
  • Clean Recipient List: Regularly verify and clean the recipient list to remove invalid addresses.
  • Review Server Logs: Examine server logs and configurations for any potential issues.
  • Evaluate Greylisting: If possible, determine if recipient domains are employing stricter greylisting policies.
  • Monitor OOf Replies: Consider if an increase in out-of-office replies coincides with the rise in bounce code 60.
  • Monitor Recipient Server Issues: Identify and resolve any issues related to the recipient server.
  • Review SES Dashboard: Review SES dashboard alerts.

What email marketers say
7Marketer opinions

An increase in bounce code 60 from SES (Amazon Simple Email Service) can stem from various factors, including transient server issues, rate limiting, spam filtering, authentication problems (SPF, DKIM, DMARC), invalid email addresses, or issues with server configuration. Community feedback suggests this bounce code is not commonly seen as an aggregate trend but can arise from temporary problems or specific configuration oversights.

Key opinions

  • Transient Issues: Bounce code 60 may indicate temporary unavailability or busyness of the recipient's server.
  • Rate Limiting: Exceeding SES sending limits can result in bounce code 60; check your sending quotas.
  • Spam Filtering: Recipient servers may be classifying emails as spam, even if they are not.
  • Authentication Issues: Problems with SPF, DKIM, or DMARC can lead to deliverability issues and bounce codes.
  • Invalid Addresses: Bounce code 60 might indicate invalid or non-existent email addresses on the recipient list.
  • Server Configuration: Issues with the server configuration, on either the sender or receiver end, may be the root cause.

Key considerations

  • Review SES Limits: Check SES sending limits and ensure they are not being exceeded.
  • Authentication Configuration: Verify that SPF, DKIM, and DMARC are correctly configured for your domain.
  • Sender Reputation: Monitor sender reputation to ensure emails are not being flagged as spam.
  • Recipient List Hygiene: Verify the email addresses on the recipient list to eliminate invalid or non-existent addresses.
  • Server Logs: Check server logs for any misconfigurations or errors.
  • Transient Nature: Recognize that the issue could be temporary and may resolve itself with retries.
Marketer view

Marketer from Email Geeks shares that they would need to look at more data, but they haven’t seen any aggregate increased trend in this behavior related to bounce code 60 from SES.

January 2024 - Email Geeks
Marketer view

Email marketer from Mailjet shares that bounce code 60 can occur due to temporary issues with the recipient's email server. It's often a transient problem that might resolve itself with retries.

February 2022 - Mailjet
Marketer view

Email marketer from SparkPost explains that although less common, bounce code 60 could sometimes indicate an invalid or non-existent email address. He suggests verifying the recipient list.

March 2023 - SparkPost
Marketer view

Email marketer from EmailOnAcid explains that authentication issues (SPF, DKIM, DMARC) can lead to deliverability problems, including bounce codes. He recommends verifying that all authentication methods are properly configured in SES.

November 2022 - EmailOnAcid
Marketer view

Email marketer from Stack Overflow suggests that bounce code 60 might be related to rate limiting on the SES account. He recommends checking the sending limits and ensuring they are not being exceeded.

July 2023 - Stack Overflow
Marketer view

Email marketer from Reddit speculates that bounce code 60 might indicate that the recipient's server is classifying the emails as spam, even if they aren't. He recommends checking sender reputation and ensuring proper authentication.

June 2024 - Reddit
Marketer view

Email marketer from AWS Forums explains that bounce code 60 can sometimes indicate a transient issue. He shares it can happen when the receiving server is temporarily unavailable or too busy to accept the message.

June 2021 - AWS Forums

What the experts say
3Expert opinions

An increase in bounce code 60 from SES could be attributed to several factors. It might be a random code for out-of-office replies, suggest configuration issues on either the sending or receiving server, or be caused by greylisting, a spam-fighting technique that results in temporary rejections.

Key opinions

  • Out of Office: Bounce code 60 from SES may be randomly assigned to out-of-office replies.
  • Server Configuration: The bounce code could indicate configuration issues with the sending or receiving server.
  • Greylisting: Increased greylisting practices may cause temporary bounces and contribute to an increase in bounce code 60.

Key considerations

  • Check OOO Replies: Consider if an increase in out-of-office replies coincides with the rise in bounce code 60.
  • Examine Server Logs: Inspect server logs and configurations for any potential misconfigurations or errors.
  • Greylisting Impact: Assess whether the recipient domains are employing stricter greylisting policies.
Expert view

Expert from Word to the Wise explains that greylisting, a spam-fighting technique, could cause temporary bounces. A receiving server may temporarily reject a message, resulting in a bounce code, and accept it upon retry. Increased greylisting could lead to more of these bounces.

March 2023 - Word to the Wise
Expert view

Expert from Email Geeks shares that bounce code 60 from SES might just be a random code assigned to out of office replies.

October 2024 - Email Geeks
Expert view

Expert from Spam Resource suggests that a bounce code 60 might indicate issues with the server configuration on either the sending or receiving end. They recommend checking server logs and configurations for any misconfigurations or errors.

January 2023 - Spam Resource

What the documentation says
4Technical articles

The SES documentation indicates that bounce code 60 is a generic error signaling issues with the recipient's server, and to check your server logs for more information. Exceeding sending limits can also cause bounce codes. SES provides bounce notifications to help interpret these issues, but RFC 3463 notes that enhanced status codes like 6.0.x are non-standard and implementation-specific.

Key findings

  • Generic Bounce: Bounce code 60 is often a generic error indicating a problem with the recipient's server.
  • Quota Limits: Exceeding sending limits or bounce quotas can result in various bounce codes.
  • Bounce Notifications: SES sends notifications to aid in interpreting bounce reasons.
  • Non-Standard Code: SMTP enhanced status codes like 6.0.x are implementation-specific and their meaning can vary.

Key considerations

  • Check Server Logs: Review server logs for more specific details about the recipient's server issues.
  • Review SES Dashboard: Monitor the SES dashboard for alerts or notifications related to sending limits or quotas.
  • Inspect Bounce Notifications: Thoroughly review SES bounce notifications for specific error codes and messages.
  • Code Variability: Be aware that the meaning of bounce code 60 may vary depending on the mail server.
Technical article

Documentation from Amazon Web Services explains that bounce code 60 can be a generic bounce indicating a problem with the recipient's server. It doesn't provide specific details but suggests checking server logs for more information.

October 2022 - Amazon Web Services
Technical article

Documentation from RFC 3463 explains that SMTP enhanced status codes such as 6.0.x are non-standard and implementation-specific, meaning their meaning can vary between mail servers. Therefore, 60 might be a custom error code.

December 2021 - ietf.org
Technical article

Documentation from Amazon Web Services details that SES sends notifications for bounces and provides guidance on interpreting these notifications, including checking the specific error codes and messages.

January 2023 - Amazon Web Services
Technical article

Documentation from Amazon Web Services states that exceeding sending limits or bounce quotas can lead to various bounce codes, and it recommends reviewing the SES dashboard for any alerts or notifications.

September 2024 - Amazon Web Services