Summary
TSS04 errors, frequently associated with Yahoo, indicate temporary email delivery issues stemming from suspected spam activity, sender reputation, or content filtering. Resolving these errors involves a multi-faceted approach: proactively ensuring robust email authentication (SPF, DKIM, DMARC), meticulous list hygiene (removing inactive or bounced addresses), carefully reviewing email content for spam triggers and testing with tools like SpamAssassin, monitoring and improving sender reputation metrics, managing sending volume and cadence, and implementing feedback loops to address recipient complaints. Segmenting Yahoo recipients, warming up IPs, checking IP blocklists, and maintaining consistent sending patterns can also mitigate TSS04 errors. If issues persist, engaging with your Email Service Provider (ESP) is recommended.
Key findings
- Yahoo Focus: TSS04 errors are disproportionately associated with Yahoo Mail and its handling of incoming emails.
- Multifactorial Causes: The root causes of TSS04 errors are multifactorial, including sender reputation, email content, sending volume, and list hygiene.
- Authentication Importance: Proper email authentication (SPF, DKIM, DMARC) is a cornerstone of preventing TSS04 errors.
- Proactive Approach: A proactive approach to email deliverability, including monitoring, testing, and list management, is crucial for minimizing TSS04 errors.
- Temporary Nature: While indicative of underlying problems, TSS04 errors are often temporary deferrals that can be resolved with prompt action.
Key considerations
- Authentication Audit: Conduct a thorough audit of your SPF, DKIM, and DMARC records to ensure proper configuration.
- List Hygiene Practices: Implement a rigorous email list cleaning process to remove inactive or bounced addresses and ensure high engagement rates.
- Content Review & Testing: Scrutinize email content for potential spam triggers and utilize testing tools like SpamAssassin.
- Reputation Monitoring: Actively monitor sender reputation metrics provided by your ESP and address any negative trends promptly.
- Volume & Cadence: Carefully manage your email sending volume and cadence to avoid overwhelming recipient servers.
- Feedback Loops: Implement feedback loops to identify and address recipient complaints and improve sender reputation.
- Yahoo Segmentation: Consider segmenting Yahoo recipients and adjusting sending strategies accordingly.
- IP Warming: Implement IP warming strategies to gradually establish a positive sending reputation with ISPs.
- Blocklist Checks: Regularly check your IP addresses against blocklists to identify and address any potential listings.
- ESP Engagement: Engage with your ESP for support and guidance on improving email deliverability and resolving TSS04 errors.
What email marketers say
7 marketer opinions
TSS04 errors, primarily encountered when sending emails to Yahoo addresses, generally indicate issues with sending reputation, volume, or email content. Multiple sources suggest improving sender reputation through IP warming, maintaining clean and engaged email lists, and consistently monitoring bounce and complaint rates. Email authentication (SPF, DKIM, DMARC) is crucial, as is ensuring email content doesn't trigger spam filters. Segmenting Yahoo recipients and sending smaller batches, along with maintaining a regular sending schedule, can also help mitigate these errors. Checking IP addresses against blocklists and working with ESPs to improve IP reputation is also advised.
Key opinions
- Reputation: TSS04 errors often stem from a poor sender reputation, particularly when sending to Yahoo.
- List Hygiene: Maintaining clean and engaged email lists is vital to avoid triggering TSS04 errors.
- Authentication: Proper email authentication (SPF, DKIM, DMARC) is essential for resolving and preventing TSS04 errors.
- Content: Email content that triggers spam filters can result in TSS04 errors.
- Yahoo Specific: TSS04 errors are often specifically related to sending to Yahoo addresses.
Key considerations
- IP Warming: Gradually warm up your IP address to build a positive sending reputation.
- Segmentation: Consider segmenting Yahoo recipients and sending smaller batches of emails.
- Monitoring: Regularly monitor bounce rates, complaint rates, and IP blocklists.
- Content A/B Testing: A/B test different subject lines and email content to identify spam triggers.
- Consistency: Maintain a regular and consistent sending schedule.
- ESP Collaboration: Work with your Email Service Provider to improve IP reputation and address potential sending issues.
Marketer view
Email marketer from Stack Overflow user responds that Yahoo's TSS04 errors often mean the sending IP has been flagged. They suggest checking the IP against blocklists and working with your ESP to improve IP reputation.
10 Jul 2024 - Stack Overflow
Marketer view
Email marketer from Gmass Blog states that TSS04 errors could indicate issues with your email content triggering spam filters. They recommend A/B testing different subject lines and content to identify and remove potentially problematic elements.
30 Jan 2023 - Gmass
What the experts say
3 expert opinions
TSS04 errors, often encountered with Yahoo, can be temporary and potentially resolved by waiting and retrying. Experts suggest that content filtering by Yahoo is a key factor, recommending the use of tools like SpamAssassin to pre-emptively identify and address problematic content. Additionally, understanding and actively utilizing feedback loops are vital for maintaining a positive sender reputation and identifying broader deliverability issues that could contribute to TSS04 errors.
Key opinions
- Temporary Nature: TSS04 errors might be temporary, suggesting a simple retry after a waiting period.
- Content Filtering: Yahoo's content filters play a significant role in TSS04-like issues.
- Feedback Loops: Active use of feedback loops is crucial for maintaining a positive sender reputation and preventing deliverability issues.
Key considerations
- Retry Strategy: If encountering a TSS04 error, consider waiting and retrying after a few hours.
- Content Testing: Test your email content with tools like SpamAssassin to identify and address potential spam triggers before sending.
- FBL Implementation: Implement and actively monitor feedback loops to understand and address recipient complaints, improving overall sender reputation.
Expert view
Expert from Email Geeks responds to a question about Yahoo and suggests waiting 4 hours and retrying due to potential TSS04 errors.
19 Jul 2023 - Email Geeks
Expert view
Expert from Spam Resource, John Levine, explains that Yahoo! Mail blocking, including issues that might lead to TSS04-like errors, is often related to content filtering and encourages senders to test their messages with services like SpamAssassin to identify potential issues before sending.
28 Jul 2022 - Spam Resource
What the documentation says
4 technical articles
TSS04 errors, primarily linked to Yahoo Mail but also impacting other platforms like Exchange Online, generally signify temporary blocking or deferral due to suspected spam activity or sender reputation issues. Key recommendations across various documentation sources include reviewing email content for spam triggers, ensuring correct configuration of SPF, DKIM, and DMARC records, maintaining a clean and engaged email list, monitoring sending reputation metrics, and adjusting sending volume and cadence. Compliance with email regulations is also crucial.
Key findings
- Spam Suspicion: TSS04 errors often indicate that outgoing mail is suspected of being spam.
- Reputation: Sender reputation significantly impacts the occurrence of TSS04 errors, particularly with Yahoo Mail.
- Email Authentication: Properly configured SPF, DKIM, and DMARC records are essential for preventing TSS04 errors.
- Temporary Issue: TSS04 errors represent temporary deferrals or blocks, suggesting an opportunity for remediation.
Key considerations
- Content Review: Carefully review email content for potential spam triggers.
- Authentication Setup: Ensure correct and complete setup of SPF, DKIM, and DMARC records.
- List Management: Maintain a clean and engaged email list to avoid reputation damage.
- Sending Volume: Review and potentially throttle sending volume to align with best practices.
- Reputation Monitoring: Actively monitor sender reputation metrics provided by your ESP.
- Compliance: Ensure compliance with all applicable email regulations (e.g., GDPR, CAN-SPAM).
Technical article
Documentation from Postmark explains that while they don't specifically list TSS04, temporary deferrals from major providers often mean examining content for anything that might be flagged as spam, reviewing your sending volume and cadence, and ensuring compliance with all email regulations.
16 Dec 2023 - Postmark
Technical article
Documentation from SendGrid explains TSS04 as a temporary deferral from Yahoo Mail due to reputation concerns. It suggests monitoring sending reputation metrics in SendGrid, improving email authentication (SPF/DKIM/DMARC), and ensuring a clean email list with engaged subscribers.
4 Apr 2022 - SendGrid
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