Summary
Increased email bounces at AT&T can be attributed to multiple factors including stricter spam filtering and blocking policies implemented by AT&T, potential blocklisting of the sender's IP address, a drop in IP reputation due to spam complaints or sudden volume increases, and issues with email authentication (SPF, DKIM, DMARC). Sending to invalid or inactive email addresses, temporary network issues at AT&T, and changes in AT&T's email server policies can also contribute to the problem. AT&T is aware of the issues and working on a fix. If the problem persists, checking blocklists, monitoring IP reputation, ensuring email list hygiene, verifying email authentication, using deliverability testing tools, and contacting AT&T are recommended.
Key findings
- Increased Blocking: AT&T has recently increased blocking of emails.
- AT&T Issue: AT&T is aware of bounce issues and working on a fix.
- Aggressive Filters: AT&T has aggressive spam filters and blocking policies.
- Potential Blocklisting: Sender's IP may be blocklisted by AT&T.
- IP Reputation: A drop in IP reputation could cause higher bounce rates.
- Authentication: Problems with SPF, DKIM, or DMARC can lead to rejection.
- Invalid Addresses: Sending to invalid addresses increases bounce rates.
- Network Issues: Temporary network issues at AT&T may cause bounces.
- Bounce Code 5.7.9: Bounce code "5.7.9 Message not accepted for policy reasons" is being observed.
- 5xx Errors: 5xx SMTP error codes indicate permanent failures.
Key considerations
- Await Fix: Wait for AT&T to resolve the ongoing issue.
- Delisting Procedures: Follow AT&T's delisting procedures if blocklisted.
- Open Ticket: Open a support ticket if the issue persists.
- Check Blocklists: Verify IP against common blocklists.
- Monitor Reputation: Monitor IP and domain reputation.
- List Hygiene: Clean email list regularly.
- Authentication: Ensure SPF, DKIM, and DMARC are correctly configured.
- Testing Tools: Use deliverability testing tools.
- Policy Changes: Stay informed of AT&T's policy changes.
- Address 5xx Errors: Investigate and resolve the underlying causes of 5xx errors.
What email marketers say
12 marketer opinions
Increased email bounces at AT&T can stem from several factors. These include AT&T's spam filtering policies and possible blocklisting, issues with IP reputation, incorrect email authentication (SPF, DKIM, DMARC), sending to invalid or inactive email addresses, temporary network issues, and changes in AT&T's email server policies. Checking blocklists, monitoring IP reputation, validating email lists, confirming proper email authentication, using deliverability testing tools, and keeping abreast of any policy changes at AT&T can help.
Key opinions
- AT&T Policies: AT&T might have stricter spam filtering or implemented new policies causing increased bounces.
- Blocklisting: Your mail server IP address could be on a blocklist, leading AT&T to reject your emails.
- IP Reputation: A drop in your IP reputation, due to spam complaints or sudden volume increases, can cause higher bounce rates.
- Authentication Issues: Problems with SPF, DKIM, or DMARC records can result in emails being rejected.
- Invalid Addresses: Sending to invalid or inactive email addresses increases bounce rates.
- Network Issues: Temporary network issues at AT&T could be causing the bounces.
- Bounce Code 5.7.9: A bounce code of "5.7.9 Message not accepted for policy reasons" is being observed.
- RBL Blocks: Some senders are experiencing blocks due to their IP being listed on Real-time Blackhole Lists (RBLs).
Key considerations
- Check Blocklists: Verify your IP address against common blocklists using online tools.
- Monitor Reputation: Monitor your IP and domain reputation to identify and address any issues.
- List Hygiene: Clean your email list regularly to remove invalid or inactive addresses.
- Authentication: Ensure your SPF, DKIM, and DMARC records are correctly configured.
- Testing Tools: Use deliverability testing tools to check email placement at AT&T and other providers.
- Policy Changes: Stay informed about any policy changes or announcements from AT&T.
- Contact AT&T: If the problem persists, contact AT&T's postmaster or abuse team for assistance.
- Monitor bounce codes: Monitor the specific bounce codes received to understand the reasons for delivery failures.
Marketer view
Email marketer from Reddit shares that a sudden increase in bounce rates can often be attributed to changes in the recipient's email server policies or increased spam filtering. They suggest checking for any recent changes at AT&T.
16 Jul 2022 - Reddit
Marketer view
Email marketer from Email Geeks shares that the bounce code they are seeing is "5.7.9 Message not accepted for policy reasons".
25 Mar 2023 - Email Geeks
What the experts say
5 expert opinions
Increased email bounces at AT&T are likely due to a problem on AT&T's side, potentially related to aggressive spam filtering or blocklisting policies. AT&T is aware of the issue and is working on a fix. If the problem persists, following AT&T's specific delisting procedures or opening a support ticket is recommended.
Key opinions
- Increased Blocking: AT&T has recently increased its blocking of emails.
- AT&T Issue: AT&T is aware of the increased bounce issues and is actively working to resolve the problem.
- Aggressive Spam Filters: AT&T is known for having aggressive spam filters and blocking policies.
- Potential Blocklisting: Your IP address may be blocklisted by AT&T.
Key considerations
- Await Fix: Wait for AT&T to resolve the issue, as they are already working on it.
- Delisting Procedures: Follow AT&T's specific procedures for requesting delisting if you suspect you are blocklisted.
- Open Ticket: If the issue persists, open a support ticket with AT&T.
- Monitor Deliverability: Continue to monitor your email deliverability to AT&T after the issue is supposedly resolved to ensure there are no further problems.
Expert view
Expert from Email Geeks shares a message that AT&T is aware of the bounce issues, and it's a problem on their side that they’re working on.
1 Dec 2024 - Email Geeks
Expert view
Expert from Spam Resource explains that AT&T is known to have somewhat aggressive spam filters and blocking policies, so increased bounces could be related to stricter filtering on their end.
3 Jul 2021 - Spam Resource
What the documentation says
4 technical articles
Increased email bounces at AT&T, indicated by 5xx SMTP error codes, signify permanent delivery failures due to reasons such as policy restrictions, spam filtering, recipient mailbox issues, or authentication problems (SPF, DKIM). Invalid or misconfigured SPF and DKIM records are common causes of rejection by receiving servers.
Key findings
- 5xx Errors: 5xx SMTP error codes indicate permanent delivery failures.
- Policy Restrictions: Bounces can result from policy restrictions or spam filtering mechanisms.
- Recipient Issues: Recipient mailbox issues may cause delivery failures.
- SPF Problems: Incorrectly configured SPF records can lead to email rejection.
- DKIM Problems: Invalid or missing DKIM signatures can cause rejection.
Key considerations
- Address 5xx Errors: Investigate and address the underlying causes of 5xx SMTP errors.
- Check Authentication: Verify and correct SPF and DKIM record configurations.
- Review Policies: Examine potential policy restrictions or spam filtering issues causing bounces.
- Invalid Recipient: Confirm the email is going to a valid and active email address.
Technical article
Documentation from RFC explains that 5xx SMTP error codes mean a permanent error. The email was not delivered and retrying will likely not help.
14 Mar 2022 - datatracker.ietf.org
Technical article
Documentation from Cisco explains that a 5xx error (like 5.7.1 or 5.7.9) indicates a permanent failure, meaning the email was not delivered. This can be due to various reasons including policy restrictions, spam filtering, or recipient mailbox issues.
3 Dec 2021 - cisco.com
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