Why am I getting TSS04 errors from Yahoo and how do I fix it?

Summary

TSS04 errors from Yahoo signify temporary delivery failures primarily due to sender reputation issues. These issues can stem from various factors including low IP reputation, high complaint rates, sending from new IPs without established reputations, sudden volume spikes, or poor sending practices. Resolving these errors involves immediately pausing sending, investigating the root cause (e.g., checking blacklists, engaging with Yahoo's postmaster resources), implementing proper email authentication (SPF, DKIM, DMARC), maintaining consistent sending volumes, segmenting lists to improve engagement, monitoring bounce rates and spam complaints, reviewing sending activities for compliance, and gradually increasing sending volume after resolution. Experts and email marketers emphasize the importance of building and maintaining a positive sender reputation with Yahoo to prevent future TSS04 errors.

Key findings

  • Reputation is Key: TSS04 errors are primarily driven by sender reputation issues.
  • Multiple Contributing Factors: Low IP reputation, high complaint rates, new IPs, and volume spikes contribute to TSS04 errors.
  • Temporary Block: TSS04 errors represent a temporary block, offering an opportunity for remediation.
  • Authentication Matters: Proper email authentication (SPF, DKIM, DMARC) is crucial for improving sender reputation and reducing errors.

Key considerations

  • Immediate Pause: Stop sending emails to Yahoo immediately upon receiving a TSS04 error.
  • Thorough Investigation: Investigate the root cause of the reputation issue, including checking blacklists and reviewing sending practices.
  • Proper Authentication: Implement and maintain proper email authentication (SPF, DKIM, DMARC).
  • Gradual Ramp-Up: Gradually increase sending volume after resolving the issue to avoid re-triggering the block.
  • Monitor Performance: Monitor bounce rates, complaints, and engagement metrics to identify and address potential issues proactively.
  • Compliance: Ensure sending practices comply with Yahoo's guidelines and policies.
  • Engage Resources: Engage with Yahoo's postmaster resources for guidance and support.

What email marketers say
9Marketer opinions

TSS04 errors from Yahoo indicate a temporary block due to issues with sender reputation, often stemming from low IP reputation, high complaint rates, sudden spikes in email volume, or sending from new IPs without established reputations. Resolving these errors involves immediately stopping sending to Yahoo, investigating and addressing the underlying causes (e.g., implementing email authentication, reducing spam complaints, gradually increasing sending volume, and pausing for an extended period), and monitoring bounce rates and engagement to ensure adherence to Yahoo's sending guidelines. Engaging with Yahoo's postmaster resources and checking blacklists are also recommended.

Key opinions

  • Reputation Issues: TSS04 errors primarily stem from sender reputation problems, including low IP reputation and high complaint rates.
  • New IPs: Sending from new IPs without a good reputation or proper verification often triggers TSS04 errors.
  • Volume Spikes: Sudden increases in email sending volume can lead to temporary blocks.
  • Authentication Matters: Lack of email authentication (SPF, DKIM, DMARC) can negatively impact sender reputation and trigger TSS04 errors.

Key considerations

  • Immediate Pause: Immediately stop sending emails to Yahoo upon receiving a TSS04 error.
  • Investigate and Resolve: Investigate the root cause of the reputation issue and implement corrective measures.
  • Gradual Ramp-Up: If adjusting sending volume, gradually increase it to avoid triggering further blocks.
  • Authentication: Ensure proper email authentication (SPF, DKIM, DMARC) is in place.
  • Monitor Engagement: Monitor bounce rates, complaints, and engagement metrics to identify potential issues proactively.
  • Postmaster Resources: Engage with Yahoo's postmaster resources for guidance and support.
Marketer view

Email marketer from Reddit indicates that TSS04 errors often occur when a new IP address begins sending emails through Yahoo or if the IP hasn't built a good reputation, which can happen through not being verified or lack of engagement. EmailHelpReddit suggests slowing down sending volumes and ensuring a good reputation by checking blacklists.

March 2021 - Reddit
Marketer view

Email marketer from Mailjet shares that improving sender reputation involves authenticating your email (SPF, DKIM, DMARC), maintaining consistent sending volumes, and segmenting your lists to send relevant content to engaged recipients to reduce complaints.

August 2024 - Mailjet
Marketer view

Email marketer from EmailOversight Blog shares that TSS04 errors are a strong indicator of IP reputation issues with Yahoo! Mail. This means your IP address may be flagged due to spam complaints, low engagement, or being a new IP with limited sending history.

July 2023 - EmailOversight Blog
Marketer view

Email marketer from Stack Overflow suggests that the TSS04 error can be a temporary block due to a sudden spike in email sending volume. It is recommended to gradually increase sending volume and monitor email sending practices.

July 2022 - Stack Overflow
Marketer view

Email marketer from Email Geeks shares TSS04 errors are most common when building reputation on a new IP/domain or if either has a poor reputation. Hassan recommends immediately stopping sending to Yahoo upon receiving a TSS04 error and pausing for at least 4 hours.

August 2024 - Email Geeks
Marketer view

Email marketer from Email Geeks indicates that this was a Yahoo issue today only, and if senders are seeing longer issues, it could be related to their mailing practices.

January 2023 - Email Geeks
Marketer view

Email marketer from SMTP2GO notes that maintaining a positive IP reputation is key to avoiding issues with Yahoo. To resolve a TSS04 error, it's important to engage with Yahoo's postmaster resources, monitor bounce rates, and adjust sending strategies to adhere to Yahoo's guidelines.

November 2022 - SMTP2GO
Marketer view

Email marketer from GMass shares that TSS04 means that the connection or IP is blocked due to complaints or other policy reasons. GMass recommends that you stop sending and contact Yahoo to resolve the reason why the IP/Domain is blocked.

August 2023 - GMass
Marketer view

Email marketer from Email Geeks shares that TSS04 usually comes due to low reputations of sending IPs and complaints, especially with new IPs. Good engagement and low complaints can resolve the issue.

January 2022 - Email Geeks

What the experts say
4Expert opinions

TSS04 errors from Yahoo signify a temporary block due to reputation problems or policy violations. Experts recommend pausing sending, lowering connection limits and delivery rates, and ensuring the pause is long enough. The errors suggest Yahoo dislikes something about your mail stream and requires investigation into reputation, complaints, or blocklisting. Immediate action involves stopping mail flow to Yahoo, reviewing recent sending activities, and checking domain and IP reputation.

Key opinions

  • Temporary Block: TSS04 errors indicate a temporary block by Yahoo, not a permanent one.
  • Reputation-Related: The underlying cause is typically related to sender reputation or policy concerns.
  • Pause is Crucial: Pausing sending is essential, and the duration must be sufficient.

Key considerations

  • Immediate Halt: Stop sending to Yahoo immediately upon receiving TSS04 errors.
  • Investigate Root Cause: Thoroughly investigate potential reputation issues, complaints, and blocklisting.
  • Review Sending Activities: Carefully review recent sending activities for any policy violations or potential issues.
  • Check Reputation: Use tools to check domain and IP reputation.
  • Ease Back In: Once resolved, gradually resume sending to Yahoo.
  • Adjust Limits: Lower connection limits and delivery rates during the ramp-up phase.
Expert view

Expert from Spam Resource explains that TSS04 errors are Yahoo's code for a temporary block. It usually means Yahoo doesn't like something about your mail stream and is putting you on hold until you fix it. Could be reputation, complaints or blocklist, so stop sending immediately, investigate, and then ease back in once you've resolved the issue.

March 2022 - Spam Resource
Expert view

Expert from Word to the Wise explains that Yahoo TSS04 errors often indicate a temporary block due to sender reputation concerns or policy reasons. Immediate action should involve stopping all mail flow to Yahoo, carefully reviewing recent sending activities, and using tools to check domain and IP reputation.

July 2022 - Word to the Wise
Expert view

Expert from Email Geeks explains if you’re still getting TSS04 errors after a pause, your pause wasn’t long enough.

May 2024 - Email Geeks
Expert view

Expert from Email Geeks explains that TSS04 errors are a temporary failure due to reputation issues. Matt recommends pausing queues for a couple of hours and lowering connection limits and delivery rates.

June 2023 - Email Geeks

What the documentation says
4Technical articles

TSS04 errors from Yahoo indicate a temporary rejection due to sender reputation issues like low IP reputation or high complaint rates. Documentation recommends pausing sending, reviewing sending practices for compliance, and implementing proper email authentication (SPF, DKIM, DMARC) to improve sender identity verification and reduce spam. Maintaining a low spam rate (below 0.10%) is also crucial to avoiding blocks.

Key findings

  • Reputation Issues: TSS04 errors are due to sender reputation issues.
  • Authentication is Key: SPF, DKIM, and DMARC improve sender identity and reduce spam.
  • Spam Rate Matters: Keeping spam rates low is crucial for good reputation.

Key considerations

  • Pause Sending: Pause sending immediately when encountering TSS04 errors.
  • Review Practices: Review sending practices for compliance and spam triggers.
  • Implement Authentication: Implement or improve SPF, DKIM, and DMARC records.
  • Monitor Spam Rate: Monitor and maintain a low spam rate (below 0.10%).
Technical article

Documentation from Google shares that to maintain a good reputation it is important to reduce your spam rate to be less than 0.10% and avoid ever reaching 0.30% as this may cause blocking.

August 2022 - Google
Technical article

Documentation from RFC explains that implementing SPF, DKIM, and DMARC helps to verify the sender's identity and reduce the chance of being marked as spam, improving sender reputation and potentially reducing TSS04 errors.

August 2023 - RFC
Technical article

Documentation from Verizon Media Postmaster explains that a TSS04 error indicates a temporary problem where Yahoo! Mail is unable to accept mail from your sending IP address due to reputation concerns. This might be triggered by low IP reputation, a high complaint rate, or other factors impacting sender reputation.

June 2022 - Verizon Media Postmaster
Technical article

Documentation from SparkPost explains that while not specifically addressing TSS04, temporary delivery failures often result from reputation-based blocking. Immediate actions include pausing sending, reviewing sending practices for compliance, and ensuring proper authentication protocols are in place.

July 2024 - SparkPost