Why are some emails to Road Runner domains experiencing delivery issues such as delays and bounces?

Key findings

• Legacy domains: Many rr.com subdomains are defunct or have been absorbed by current cable providers such as Charter/Spectrum and Comcast. Identifying the specific Road Runner subdomain is essential.
• Sporadic delivery: Common symptoms include messages arriving very late (up to 24 hours) or experiencing soft bounces.
• Bounce codes: Specific error messages like 4.4.2 (bad connection) indicate connection or temporary server issues at the recipient's end.
• Sender reputation: Issues can also arise from a poor sender reputation, which can lead to blocks or deferrals, as discussed in our guide on Road Runner deferrals and rejections.
• Spam origination: Some spam has been observed originating from unresolvable rr.com domains via major email providers like Google/Gmail.

Key considerations

• Examine bounce messages: Detailed analysis of bounce messages and their codes can reveal specific patterns and causes.
• Perform MX lookups: Use MX lookups on the problematic rr.com subdomains to determine which mail service is currently handling their email, as tools.wordtothewise.com/dns/ facilitates.
• Analyze email headers: Requesting and reviewing full email headers for delayed messages can pinpoint where delays are occurring within the mail path.
• Review ESP logs: Work with your Email Service Provider (ESP) to thoroughly investigate what is happening during the SMTP transaction.

Key opinions

• Customer blame: Customers are quick to blame the sender for intermittent delivery issues to rr.com addresses, even if the problem lies with the recipient ISP.
• Inconsistent reporting: Marketers find it challenging to get consistent deliverability insights from their ESPs, making it hard to compare performance for these specific domains across different platforms.
• Data discrepancies: Observed open tracking timestamps might contradict customer claims of significant email delays, suggesting a need for deeper data analysis.
• Persistent user base: A surprising number of customers still use old rr.com email addresses, even in regions where Road Runner services were not historically prevalent.

Key considerations

• Trust data over anecdote: Prioritize hard data from bounce messages and email headers for accurate troubleshooting, rather than solely relying on customer reports.
• Strategic domain management: Consider carefully managing or phasing out addresses on consistently problematic rr.com subdomains that show no signs of active delivery. You can learn more about this in our article on email deliverability issues.
• ESP collaboration: Work closely with your ESP to obtain detailed SMTP transaction logs and identify specific points of failure.
• Customer service training: Equip customer service with accurate information about potential external factors affecting email delivery to these legacy domains.

Key opinions

• Domain status: Many rr.com domains are now inactive, while others have been migrated to current cable providers, requiring senders to identify the actual mail handler.
• MX record importance: Performing MX lookups is critical for determining which entity (e.g., Charter, Comcast) is currently responsible for mail handling for specific rr.com subdomains. Our guide to improving email deliverability highlights similar diagnostic steps.
• Unusual MX configurations: Some rr.com subdomains might exhibit unusual MX records that are not typical for their apparent current owners, such as Charter.
• SMTP transaction analysis: Experts recommend a deep dive into SMTP transaction logs to understand precisely what is occurring during email delivery attempts.
• Geographic history: Road Runner (and its subdomains) had varying geographic presences, with some domains (e.g., socal.rr.com, san.rr.com) being active in certain California markets prior to acquisitions.

Key considerations

• Leverage diagnostic tools: Utilize DNS lookup tools to identify current MX handlers for problematic domains, as suggested by experts from Word to the Wise.
• Collaborate with postmasters: Direct communication with the postmaster teams of current mail handlers (like Charter/Spectrum) can be effective for resolving specific issues.
• Analyze received headers: Thoroughly examine Received headers in delayed emails to trace the exact point of delay.
• Understand blocklists: Familiarize yourself with how blacklists and blocklists operate, as this is often a factor in delivery issues. Our guide, an in-depth guide to email blocklists, provides comprehensive information.

Key findings

• ISP consolidation: Major ISPs like Spectrum (Charter, Brighthouse, Time Warner) have absorbed many legacy domains, leading to a complex and sometimes inconsistent mail routing.
• Rate limits and queuing: Email messages may be accepted by an ESP but queued internally due to rate limits, causing significant delivery delays.
• Content and format issues: Oversized emails, incorrect file formats, and spam-like content are common reasons for emails to be bounced or blocked by recipient servers.
• Sender address matching: Some systems, particularly older ones, may require strict matching between the sender address and the 'from' address in the email headers.

Key considerations

• Adhere to standards: Ensure your email sending practices and formats align with RFC 5322 and other relevant email standards to minimize rejection risks. This is critical for improving your email deliverability rates.
• Monitor sending volume: Implement strategies to monitor and manage your sending volume to avoid exceeding ISP rate limits, which can lead to deferrals.
• Optimize content: Regularly review your email content, including attachments and formatting, to avoid triggering spam filters at the recipient's end.
• Maintain sender reputation: A strong sender reputation is fundamental for consistent inbox placement across all ISPs, including those managing legacy Road Runner domains. Our article on recovering domain reputation offers relevant insights.