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      Ensuring Successful Newsletter Delivery during ESP Migration

      New to Letterhead? Please read through this article to know what you can do now to smoothly transition your existing newsletter over to Letterhead.

      Introduction

      Welcome to Letterhead! We're thrilled to have you on board. This guide is designed to help you navigate the migration process from your current Email Service Provider (ESP) to Letterhead, ensuring that your emails continue to reach your subscribers' inboxes. Whether you're new to email newsletters or an experienced sender, this guide will provide you with step-by-step instructions and best practices to maintain high deliverability and avoid common pitfalls.

      Initial Migration Phase

      1.  Decide on Subdomain Usage

      What is a Subdomain?

      A subdomain is a prefix added to your main domain name, creating a separate segment for sending emails, e.g., news.domain.com or email.domain.com.

      Why Use a Subdomain?

      • De-risking Your Primary Domain: Using a subdomain for email sending helps protect your primary domain's reputation. If the subdomain encounters deliverability issues, your main domain (used for your website, sales team, etc.) remains unaffected.
      • Isolation of Issues: If another department or an external actor does something malicious, it won't impact the primary domain's reputation.
      • Best Practice for Domain Health: Helps isolate and manage email reputation independently from your main domain.

      2. Verify DMARC, DKIM, and SPF Records

      What are these?

      DMARC (Domain-based Message Authentication, Reporting, and Conformance), DKIM (DomainKeys Identified Mail), and SPF (Sender Policy Framework) are authentication protocols that help protect your email domain from being used in phishing and spam attacks.

      Verification Process

      1. Use tools like MXToolbox to check if your DMARC, DKIM, and SPF records are correctly set up.
      2. Fixing DMARC Policy Not Enabled Error: Follow the guide on PowerDMARC to resolve this issue.

      Important Note for Letterhead Users: While Letterhead verifies and handles DMARC, DKIM, and SPF on our side as your ESP, you must ensure these records are correctly set up on your domain. If your DMARC, DKIM, or SPF has not been verified yet, you need to make sure it is active. Letterhead can confirm that these records are correct, but keeping them updated is crucial for optimal deliverability.

      Health Check

      Before migrating, run a health check on your domain to ensure it's not on any spam lists and that it has no inactive subscribers. Clean up your email list to avoid migrating bad emails to the new platform. Use tools like NeverBounce or ZeroBounce for list verification.

      3. Assess Domain Health and Reputation

      Why it's Important

      A good domain reputation ensures your emails are less likely to be marked as spam.

      Tools and Methods

      Common Reasons for Poor Reputation

      • High bounce rates, spam complaints, sending to inactive emails, or not sending emails for a long time and suddenly resuming.
      • Automated campaigns with poor engagement.
      • Different ESPs handle email content differently, which can impact deliverability.

      Address Issues

      Follow recommendations from these tools to improve your domain health. Improvements can take from a few weeks to several months, depending on the severity and consistency of your practices.

      4. Check for Blacklists

      What are Blacklists?

      Blacklists are databases of IP addresses or domains known to send spam. If your domain or IP is listed, your emails are likely to be blocked or marked as spam by many ESPs.

      How to Check

      Use tools like MXToolbox or Spamhaus to see if your domain or IP is blacklisted.

      Common Scenarios Leading to Blacklisting

      • Accidental: High bounce rates, spam complaints, or sending to inactive emails.
      • Malicious: If your domain is hacked and used to send spam.

      Steps to Take if Blacklisted

      1. Follow the removal process specified by the blacklist service.
      2. Improve your email practices, such as maintaining a clean list and ensuring high engagement, to avoid future blacklisting.

      How Often to Check

      Check your domain or IP status quarterly or at least once a year.

      5. Gradual IP Warming

      Explanation

      IP warming is the process of gradually increasing the volume of mail sent with a dedicated IP address according to a predetermined schedule. This helps build a good sender reputation with ISPs.

      Learn More About IP Warming: SparkPost IP Warm-Up Overview.

      Detailed Strategy

      • Day 1-3: Start Slow
        • Send 0.5-1% of your total list per day, starting with 20-50 emails to your most engaged subscribers.
      • Day 4-7: Gradually Increase Volume
        • Increase to 1-2% of your total list, including some less active but still engaged recipients.
      • Week 2: Moderate Increase
        • Increase to 5-10% of your total list, including a broader segment of your list.
      • Week 3: Higher Volume
        • Increase to 10-20% of your total list, focusing on high engagement rates.
      • Week 4 and Beyond: Full Send Volume
        • Gradually reach your full intended volume, depending on your total list size and engagement levels.

      Content Strategy

      Use high-quality, engaging content that encourages opens and clicks. Examples include personalized messages, special offers, and exclusive content.

      Special Considerations

      • List Size Consideration:
        • For smaller lists (under 10,000 subscribers), start with smaller percentages and shorter warming periods.
        • For larger lists (over 100,000 subscribers), extend the warming period and use smaller increments.
      • Frequency Adjustments:
        • If you send weekly or monthly newsletters, increase the volume incrementally per campaign rather than daily.

      6. Monitor

      Track open rates, click rates, and bounce rates regularly, monitoring any large spikes in percentage changes.

      Common Issues and Their Causes

      Emails Landing in Spam

      Why It Happens

      • Switching ESPs can temporarily affect email deliverability, though this can often be resolved after a short period of time without any lasting consequences.
      • Firewalls, spam filters, and past user actions (e.g., marking emails as spam) can cause issues.
      • Content that includes spammy words or high scrutiny from email clients or AI filtering.

      Gmail Tabs Check

      Use the Litmus Gmail Category Tab Test to see which tab your email is likely to land in.

      Scenario Analysis

      • Few Subscribers (1-2) Reporting Spam:
        • Verify the percentage of affected subscribers.
        • Check if affected subscribers belong to the same email domain.
      • Significant Number of Subscribers (3%+) Reporting Spam:
        • Immediate steps to take: Verify DNS records, check email content for spam triggers, review recent changes in sending practices.

      Decision Tree

      1. Initial Checks:
        • Check the volume of spam complaints.
        • For low volume, send a canned response guiding subscribers to check their spam/junk folders and mark your emails as "Not Spam."
      2. Higher Volume Issues:
        • Check your Letterhead dashboard for anomalies.
        • If there's a large spike (over 2-3%) in blocked or spam reports, contact Letterhead support.
        • Verify DMARC, DKIM, and SPF records are correctly set up.
        • Run your email through a spam checker tool to ensure no spammy content or links.
      3. Detailed Checks:
        • Look for complaint patterns (e.g., all from Yahoo, Gmail, or a specific domain).
        • Ensure no major changes in email content or structure might trigger spam filters.
      4. Final Steps:
        • If issues persist, suggest subscribers contact their IT department to check for firewalls or other blocking mechanisms.
        • Consider sending emails through a different email client or a different email address to see if the issue persists.

      Bounces and Soft Bounces

      When to Be Concerned

      • Low Bounce Rates (under 2%): Typically normal, no action needed.
      • Moderate Bounce Rates (2-5%): Monitor and verify list health.
      • High Bounce Rates (over 5%): Immediate action is required.

      Decision Tree

      1. Are bounces predominantly soft (temporary issues) or hard (permanent issues)?
        • Soft Bounces: Check email server status and retry later.
        • Hard Bounces: Clean your email list of invalid addresses, ensure proper email collection practices.
      2. Tools for Analyzing Bounce Reasons:
        • Use your ESP's reporting tools to get detailed bounce reasons.
        • Consider third-party tools like NeverBounce or ZeroBounce.

      Best Practices for All Times

      Maintain Clean Email Lists

      • Regularly clean and update email lists.
      • Remove inactive or unengaged subscribers.

      Content Best Practices

      • Craft engaging, non-spammy content.
      • Avoid common spam triggers.
      • Resource on Spam Words: Campaign Monitor's Guide to Spam Words
      • Specific Spam Words to Avoid:
        • Examples include: "free," "guarantee," "urgent," "winner," "buy now," "cash bonus," and "click here."

      Engagement Metrics

      • Keep an eye on open rates, click rates, and bounce rates.
      • Adjust strategies based on these metrics.
      • Effective Engagement Strategies:
        • Personalize your emails.
        • Segment your audience for targeted messaging.
        • Use compelling subject lines and preheaders.

      Ongoing Monitoring and Support

      Test Sends

      • Conduct thorough tests before full-scale sending.
      • Best practices for test emails:
        • Send test emails to a variety of email clients (Gmail, Outlook, Yahoo, etc.).
        • Check for rendering issues and spam filter triggers.

      Continuous Monitoring

      • Use deliverability tools to monitor performance.
      • Regular checks on domain health and blacklists.
      • Best Tool for Continuous Monitoring: Email on Acid or Litmus

      Contacting Support

      How and when to reach out to Letterhead's support team for help:

      • Reach out if you notice significant drops in open rates, sudden spikes in bounce rates, or consistent deliverability issues.
      • Prepare information such as recent email campaign details, bounce reports, and any error messages received.

      Troubleshooting Guide for Letterhead Customers

      Scenario: A subscriber reports not receiving your newsletter

      1. Check the subscriber's profile in your newsletter to confirm an active subscription and recent activity (opens, clicks).
      2. If the subscriber is active but does not see the newsletter, there may be an issue with the email client's spam filters. Advise them to add your sending address to their contacts and check their spam folder.
      3. Check for any unusual spikes in spam complaints or bounces in your recent campaigns. If there are significant increases, investigate further:
        • Check if your domain has been flagged on any spam lists using tools like MXToolbox or Spamhaus.
        • Use tools like Email on Acid to check if your recent campaigns are triggering spam alerts.
        • Review your email content for any trigger words, suspicious links, or other issues that could be causing the problem.
      4. If you can't resolve the issue, have the subscriber unsubscribe and re-subscribe, confirming their subscription via the confirmation message.
      5. If the problem persists, contact Letterhead support, providing details about the affected subscriber(s), campaign(s), and any actions taken to troubleshoot the issue.

      Scenario: A significant portion of your subscribers are not receiving your newsletters

      1. Check your ESP dashboard for any unusual spikes in bounce rates or spam complaints. If you notice a significant increase (e.g., over 5% bounce rate or 1% spam complaints), investigate further.
      2. Verify that your DMARC, DKIM, and SPF records are correctly set up and have not been modified recently. Incorrect or missing authentication records can lead to deliverability issues.
      3. Use tools like MXToolbox or Spamhaus to check if your sending domain or IP has been blacklisted. If listed, follow the removal process and take steps to improve your email practices.
      4. Analyze your email content using tools like Email on Acid or Litmus to identify potential spam triggers, such as spammy words, excessive links, or large images.
      5. If the issue persists and affects a significant portion of your subscribers, contact Letterhead support, providing details about the affected campaigns, bounce rates, spam complaints, and any actions taken to troubleshoot the issue.

      Scenario: Open rates have dropped significantly compared to previous campaigns

      1. Verify that your email content is rendering correctly across different email clients and devices. Use tools like Litmus or Email on Acid to preview your emails and identify any rendering issues.
      2. Check if there have been any recent changes to your email design, subject lines, or sending schedule that might have affected engagement.
      3. Analyze your subject lines and preheader text to ensure they are compelling and not misleading. Avoid using spammy or clickbait-style subject lines.
      4. Consider segmenting your audience based on engagement levels and sending targeted campaigns to re-engage inactive subscribers.
      5. If the drop in open rates is substantial and cannot be attributed to any specific changes in your email strategy, contact Letterhead support for further assistance.

      Scenario: Click-through rates have decreased, but open rates remain stable

      1. Review your email content to ensure that your calls-to-action (CTAs) are clear, prominent, and enticing. Use action-oriented language and make sure your CTAs stand out visually.
      2. Check that all links in your email are working correctly and lead to the intended destinations. Broken or misleading links can discourage clicks.
      3. Analyze the relevance and value of your email content. Are you providing content that resonates with your subscribers' interests and needs? Consider surveying your audience to gather feedback on the types of content they would like to receive.
      4. Experiment with different CTA placement, design, and copy to optimize click-through rates. Use A/B testing to determine which variations perform best.
      5. If you have made significant changes to your email content or template and click-through rates have not improved, reach out to Letterhead support for guidance on best practices and optimization strategies.

      When to Troubleshoot on Your Own vs. When to File a Ticket

      • If you notice minor fluctuations in bounce rates, spam complaints, or engagement metrics, the first attempt to troubleshoot the issue using the steps outlined above.
      • If the issue affects a small number of subscribers (e.g., less than 1% of your list) and you can resolve it by following best practices or making minor adjustments to your email strategy, there is no need to file a ticket.
      • However, if you experience a significant or sudden increase in bounce rates (over 5%), spam complaints (over 1%), or a drastic drop in engagement metrics that changes in your email practices cannot explain, contact Letterhead support for assistance.
      • When filing a ticket, provide as much detail as possible, including the affected campaigns, specific metrics (bounce rates, spam complaints, open rates, click-through rates), any error messages, and the steps you have already taken to troubleshoot the issue. This information will help the support