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Troubleshooting Email Delivery Issues

If you're experiencing problems with email delivery in SendSquared, this guide will help you identify and resolve common issues that might prevent your emails from being sent or received correctly.

Common Email Delivery Problems​

Users typically encounter the following email-related issues:

  • Emails not being sent
  • Delayed delivery
  • High bounce rates
  • Emails landing in spam folders
  • Formatting or display problems
  • Image loading failures

Quick Diagnosis​

Before diving into detailed troubleshooting, check these common causes:

  1. Verify System Status

  2. Review Recent Campaign Reports

    • Look for unusual bounce rates or delivery issues in your campaign analytics

  3. Check Sending Limits

    • Ensure you haven't exceeded your account's daily sending limits

Step-by-Step Troubleshooting​

1. Resolving "Email Not Sent" Issues​

If your emails aren't being sent at all:

  1. Check Email Quota

    • Navigate to Account Settings > Email Usage
    • Verify you have sufficient quota remaining
    • If you've reached your limit, contact your administrator to increase your quota

  2. Verify Recipient Lists

    • Ensure recipient email addresses are correctly formatted
    • Check for and remove any obviously invalid addresses
    • Confirm your suppression lists aren't blocking intended recipients

  3. Review for Compliance Issues

    • Ensure your email content doesn't contain trigger words commonly associated with spam
    • Check that you have a valid unsubscribe link
    • Verify your sending domain is properly authenticated

2. Addressing Delivery Delays​

If emails are sending but taking longer than expected:

  1. Check Campaign Size

    • Large campaigns are automatically throttled to maintain deliverability
    • Consider breaking very large campaigns into smaller segments

  2. Review Email Size

    • Emails with large attachments or many images may process more slowly
    • Optimize images and limit attachment sizes

  3. Verify Sending Domain Health

    • Navigate to Account Settings > Domains
    • Ensure all authentication records (SPF, DKIM, DMARC) show as "Verified"
    • If any are showing errors, follow the provided instructions to fix them

3. Reducing Bounce Rates​

If you're experiencing high bounce rates:

  1. Analyze Bounce Reports

    • Navigate to Campaigns > [Your Campaign] > Analytics > Bounces
    • Review the specific bounce reasons provided

  2. Address Hard Bounces

    • Remove invalid email addresses from your lists
    • Update contact information for accounts with changed email addresses

  3. Resolve Soft Bounces

    • For "mailbox full" responses, try resending after a few days
    • For "server unavailable" errors, verify the domain is valid

  4. Monitor Contact Verification Status

    • SendSquared automatically verifies and cleans your contact lists to reduce bounces

    • To check your current verification status:

      a. Navigate to Global Settings > Contact Verification Status

      b. Review the verification dashboard which shows:

      • Percent of contacts verified (overall percentage of verified contacts)
      • Percent of contacts valid (contacts that can receive emails)
      • Percent of contacts invalid (contacts with problematic email addresses)

      c. You'll see both percentages and actual counts (e.g., "12557/17991" verified contacts)

      d. Use the "View Verified" and "View Unverified" buttons to see detailed lists

      e. Pay special attention to the invalid percentage—a rate above 15% could negatively impact deliverability

      f. Consider removing invalid contacts from your regular sending lists to improve delivery rates

4. Preventing Spam Folder Placement​

If your emails are landing in recipients' spam folders:

  1. Improve Content Quality

    • Avoid excessive use of sales language or all caps
    • Maintain a good text-to-image ratio
    • Ensure links point to reputable domains

  2. Perfect Your Authentication

    • Implement all recommended authentication methods (SPF, DKIM, DMARC)
    • Navigate to Account Settings > Domains to verify all records

  3. Build Sender Reputation

    • Send consistently rather than in large, infrequent batches
    • Target engaged subscribers who have opened your emails recently
    • Gradually increase volume when sending to new lists

5. Fixing Email Display Issues​

If your emails aren't displaying correctly:

  1. Test Across Email Clients

    • Use the Email Preview tool (Campaigns > Create/Edit > Preview)
    • Test across multiple devices and email clients

  2. Fix Common Rendering Problems

    • Ensure images have alt text
    • Use mobile-responsive templates
    • Keep table structures simple

  3. Troubleshoot Image Loading

    • Verify images are properly hosted and accessible
    • Ensure image file sizes are optimized for email (under 200KB per image)
    • Check that image paths are absolute rather than relative

Advanced Troubleshooting​

For persistent delivery issues:

  1. Review Email Headers

    • Ask a recipient to forward you the full email headers
    • Analyze delivery path and authentication results

  2. Check Blacklist Status

    • Navigate to Account Settings > Domains > Reputation
    • Verify your sending domain and IP aren't on major blacklists
    • Follow provided remediation steps if blacklisted

  3. Analyze Engagement Metrics

    • Low open rates may indicate deliverability problems
    • Review historical engagement trends for patterns

Getting Additional Help​

If you've completed all troubleshooting steps and still experience issues:

  1. Gather Information

    • Document the specific symptoms you're experiencing
    • Collect error messages, bounce notifications, and affected recipient domains
    • Note any recent changes to your sending practices

  2. Contact Support

    • Reach out via the "Get in touch" button on status.sendsquared.com
    • Provide detailed information about the steps you've already taken
    • Include campaign IDs, sending times, and recipient examples (with consent)

Best Practices to Prevent Future Issues​

  1. Maintain List Hygiene

    • Regularly review your Contact Verification Overview (Global Settings > Contact Verification Status)
    • Focus on improving your valid contact percentage by removing invalid addresses
    • Aim to keep your invalid contact percentage below 10% for optimal deliverability
    • Immediately honor unsubscribe requests
    • Implement double opt-in for new subscribers

  2. Monitor Deliverability Metrics

    • Review bounce, open, and click rates for each campaign
    • Watch for sudden changes that might indicate problems

  3. Stay Informed

    • Follow SendSquared's deliverability blog for updates
    • Attend webinars on email best practices