Summary
Email delivery issues to Road Runner domains are complex, stemming from a confluence of factors. Road Runner's convoluted history, involving acquisitions and transitions to providers like Spectrum, Charter, and Time Warner Cable, has resulted in many defunct domains and ongoing mailbox migrations. This, combined with aggressive spam filtering, potential server connection problems, and shared network infrastructure (AS11427), contributes to delivery challenges. Crucially, proper sender authentication (SPF, DKIM, DMARC) is essential, as is avoiding spam trigger words and maintaining good email formatting. Analyzing email headers and understanding SMTP transactions are vital for troubleshooting. Ultimately, proactive monitoring, adherence to email best practices, and collaboration with ESPs are key to mitigating these issues.
Key findings
- Domain & Provider Transitions: Road Runner's transitions to Spectrum/Charter have led to mailbox migrations and inconsistent DNS updates.
- Domain Status: Many Road Runner domains are either actively dead or inactive.
- Spam Filtering: Aggressive spam filtering by Spectrum can misclassify legitimate emails.
- Authentication Failures: Lack of SPF, DKIM, and DMARC authentication increases the likelihood of emails being marked as spam.
- DNS Resolution Issues: Incorrect MX records or server outages can lead to delays and bounces.
- Shared IP Infrastructure: Routing through AS11427 can lead to shared IP reputation issues and potential blocklisting.
- Email Content Triggers: Using spam trigger words or having poor email formatting affects deliverability.
Key considerations
- ESP Collaboration: Work closely with your ESP to investigate SMTP transactions and troubleshoot delivery issues.
- Authentication Implementation: Ensure that SPF, DKIM, and DMARC are correctly configured.
- Content Review: Review email content to avoid spam trigger words and poor formatting.
- MX Record Verification: Regularly check MX records to ensure they point to the correct mail servers.
- Subdomain Monitoring: Pay close attention to specific Road Runner subdomains and phase out non-delivering ones.
- Header Analysis: Analyze email headers of bounced or delayed messages to identify the source of the problem.
- IP Reputation Monitoring: Monitor your IP and domain reputation to ensure they aren't on any blocklists.
- Warm Up IP Addresses: Warm up IP addresses when introducing them
What email marketers say
8 marketer opinions
Delivery issues to Road Runner domains stem from a combination of factors, including domain transitions to Spectrum, aggressive spam filtering, potential server connection problems, and sender-side misconfigurations. Proper sender authentication (SPF, DKIM, DMARC) is crucial, as is avoiding spam triggers in email content. The age of the domain and the transfers between parent companies adds an extra layer of complexity.
Key opinions
- Domain Transitions: Road Runner's transition to Spectrum may cause intermittent issues due to mailbox migrations and DNS updates.
- Spam Filtering: Aggressive spam filtering by Spectrum can misclassify legitimate emails, leading to delivery problems.
- Server Issues: Occasional server connection issues at the recipient's end can cause temporary delays or bounces.
- Authentication Protocols: Lack of proper sender authentication (SPF, DKIM, DMARC) increases the likelihood of emails being marked as spam.
- Content Triggers: Spam trigger words or poor email formatting can negatively affect deliverability.
- Header Analysis: Header samples of delayed or bounced emails can help identify the source of the problem.
Key considerations
- Authentication Implementation: Ensure SPF, DKIM, and DMARC are correctly configured to authenticate your emails.
- Content Optimization: Review email content to avoid spam trigger words and ensure proper formatting.
- IP Warming: Implement a gradual IP warm-up strategy when using new IP addresses.
- Header Analysis: Analyze email headers to identify the source of delays or bounces and troubleshoot the issue.
- Best Practices: Adhere to general email marketing best practices to improve sender reputation and avoid spam filters.
Marketer view
Email marketer from Sendinblue highlights that if you are not warming your IP address correctly this will affect deliverability. Make sure you have an IP warm up strategy in place when using a new IP address.
17 May 2024 - Sendinblue
Marketer view
Email marketer from Email Geeks suggests that the received headers will be helpful.
15 Mar 2022 - Email Geeks
What the experts say
5 expert opinions
Delivery issues to Road Runner domains are complex and multifaceted. A significant portion of the problems arise from the domain's complicated history involving various acquisitions and migrations to different cable providers (Spectrum, Charter, Time Warner Cable). Many Road Runner domains are either defunct or have transitioned, necessitating careful monitoring of individual subdomains. Network infrastructure issues, such as the shared AS11427 routing for these providers, can lead to widespread IP reputation problems. Moreover, DNS configuration errors (SPF, DKIM, DMARC) frequently contribute to bounces. A thorough understanding of the SMTP transaction and leveraging tools for MX lookups is also key to diagnosing and resolving these delivery challenges.
Key opinions
- Domain Status: Many Road Runner domains are inactive or have been transferred to other providers.
- Subdomain Variance: Individual Road Runner subdomains operate quasi-independently, requiring focused attention.
- Shared Infrastructure: Routing through AS11427 can lead to IP reputation issues affecting large IP blocks.
- DNS Configuration: Incorrect or missing DNS records (SPF, DKIM, DMARC) can cause delivery failures.
- SMTP Issues: Problems arising during the SMTP transaction contribute to delivery challenges.
Key considerations
- Subdomain Monitoring: Closely monitor the delivery performance of individual Road Runner subdomains and phase out non-delivering ones.
- MX Lookups: Use MX lookups (via dig or online tools) to determine which provider currently handles mail for specific Road Runner domains.
- ESP Collaboration: Work with your ESP to investigate the SMTP transaction when encountering delivery issues.
- DNS Configuration: Ensure correct configuration of SPF, DKIM, and DMARC records.
- Blocklist Monitoring: Monitor your IP and domain reputation to ensure they are not on any blocklists.
Expert view
Expert from Email Geeks shares how to identify who is handling the mail for Road Runner domains by doing MX lookups. Suggests using dig or online tools like tools.wordtothewise.com/dns/ to perform the lookups.
24 Sep 2023 - Email Geeks
Expert view
Expert from Email Geeks explains that many Road Runner domains are actively dead or moved to other cable providers. She suggests paying close attention to specific subdomains and phasing out those without delivery. Also suggests investigating bounce messages to identify patterns.
20 Apr 2025 - Email Geeks
What the documentation says
4 technical articles
Email delivery issues to Road Runner domains can be attributed to several technical factors. Incorrect email server settings, as pointed out by Spectrum Support, can disrupt both sending and receiving. Spamhaus emphasizes the crucial role of sender reputation; a poor reputation due to spam complaints or blocklisting leads to delivery failures. DNS resolution problems, including incorrect MX records or server outages (according to the RFC Editor), also cause delays and bounces. MXToolbox further suggests checking for DNS issues, blocklisting, and overall email server health using their tool, as these problems can lead to deliverability problems.
Key findings
- Server Settings: Incorrect email server settings can disrupt email flow.
- Sender Reputation: Poor sender reputation leads to delivery failures.
- DNS Resolution: DNS resolution problems cause delays and bounces.
- Server Health: Problems with email server health may result in deliverability problems.
Key considerations
- Verify Settings: Double-check and correct email server settings.
- Reputation Management: Monitor and maintain a good sender reputation by adhering to email best practices.
- DNS Configuration: Ensure correct DNS configuration, especially MX records.
- Health Checks: Use tools like MXToolbox to routinely check for DNS issues, blocklisting, and server health problems.
Technical article
Documentation from Spamhaus indicates that poor sender reputation, often due to spam complaints or being listed on blocklists, can lead to email delivery failures. Monitoring and maintaining a good sender reputation is vital.
15 Jul 2021 - Spamhaus
Technical article
Documentation from Spectrum Support highlights that incorrect email server settings (incoming/outgoing mail servers, ports, authentication) can cause sending and receiving problems. Verifying these settings is crucial for resolving delivery issues.
30 Apr 2025 - Spectrum Support
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