TABLE OF CONTENTS

Resolving Blacklisted URL/IP/Domain Email Blocks

What's Happening?

Your emails are being blocked because one or more components in your email campaign have been flagged by public blacklists (RBLs/DBLs). This could be your sending IP address, your domain, or URLs included in your email content. Email providers use these blacklists as a first line of defense against spam, and being listed can severely impact your email deliverability across multiple platforms.

Quick Diagnosis: Identifying Blacklist Issues

Bounce Message Examples

  • Email blocked due to listed URLs or IPs/domains on public blacklists (RBLs/DBLs).

Understanding Blacklist Blocks

Key Concepts

Important Information:

  • Blacklists are third-party databases that track suspicious IPs, domains, and URLs
  • Major email providers (Gmail, Outlook, Yahoo) consult multiple blacklists before accepting emails
  • Being blacklisted affects ALL emails from your account, not just specific campaigns
  • Blacklist removal can take 24-72 hours even after resolving the underlying issue
  • Some blacklists automatically remove entries after a period of good behavior

Common Blacklist Types

IP-Based Blacklists (RBLs):

  • Spamhaus SBL/CSS/XBL/PBL - Most widely used
  • Barracuda Reputation Block List
  • SURBL - Focuses on spam URLs
  • SpamCop - Community-driven reporting

Domain/URL Blacklists (DBLs):

  • Spamhaus DBL - Domain reputation
  • URIBL - URL reputation tracking
  • SURBL - Spam URL realtime blocklist
  • Google Safe Browsing - Malware/phishing protection

Step-by-Step Blacklist Resolution

Step 1: Identify What's Blacklisted

Check Your Sending Infrastructure:

  1. Find your sending IP:
    • Go to Settings → Email Services → Sending Domain and IP
    • Note your configured sending domain and any IP information displayed
    • If using shared infrastructure, contact support for IP details
  2. Use external blacklist checkers:
    • Visit MXToolbox.com → Blacklist Check
    • Enter your sending IP address
    • Check your sending domain separately
    • Test any URLs frequently used in your campaigns

Step 2: Analyze Email Content

Review Recent Campaigns:

  1. Access your campaign history:
    • Go to Marketing → Emails → Campaigns
    • Review campaigns sent in the last 7-14 days
    • Look for any new URLs, domains, or shortened links
  2. Check for problematic content:
    • Shortened URLs (bit.ly, tinyurl, etc.)
    • Newly registered domains
    • URLs with suspicious extensions (.tk, .ml, .ga)
    • Links to file-sharing services

Step 3: Submit Delisting Requests

Contact Blacklist Operators:

  1. For Spamhaus listings:
    • Visit spamhaus.org → SBL/CSS/PBL Removal
    • Enter your IP/domain and follow removal process
    • Provide detailed explanation of remediation steps
  2. For other major blacklists:
    • Barracuda: barracudacentral.org/rbl/removal-request
    • SpamCop: spamcop.net → Reporting → Remove
    • SURBL: surbl.org → Whitelist Request

Successful Delisting Indicators

  • Blacklist checker shows "Not Listed" status
  • Test emails reach inbox instead of bouncing
  • Bounce rates return to normal levels (under 2%)
  • Email delivery reports show improved acceptance rates

Step 4: Implement Preventive Measures

Strengthen Your Email Practices:

  1. Update email templates:
    • Go to Marketing → Emails → Templates
    • Remove any flagged URLs or domains
    • Replace shortened URLs with full, reputable links
    • Add clear unsubscribe links and physical addresses
  2. Improve list hygiene:
    • Go to Contacts → Smart Lists
    • Create segments for engaged subscribers only
    • Remove bounced and unengaged contacts regularly

Recovery Timeline and Expectations

Phase 1: Immediate Actions (0-24 hours)

  • Action: Identify blacklisted components and submit removal requests
  • Expected outcome: Confirmation of blacklist status and removal request submission

Phase 2: Delisting Process (24-72 hours)

  • Action: Monitor blacklist status and follow up on removal requests
  • Expected outcome: Gradual removal from blacklists, improved delivery rates

Phase 3: Reputation Recovery (1-4 weeks)

  • Action: Maintain clean sending practices and monitor deliverability
  • Expected outcome: Full restoration of email deliverability and sender reputation

Ongoing Monitoring and Prevention

Weekly Monitoring Routine

  1. Check blacklist status:
    • Use MXToolbox.com weekly blacklist monitoring
    • Set up alerts for any new listings
    • Monitor Sender Score at senderscore.org
  2. Review metrics:
    • Go to Reporting → Email Analytics
    • Monitor bounce rates (should stay under 2%)
    • Watch for sudden delivery rate drops

Best Practices for Prevention

Content Guidelines:

  • Use your own domain for all links when possible
  • Avoid URL shorteners unless absolutely necessary
  • Test all URLs before including in campaigns
  • Maintain consistent sending patterns and volumes
  • Include clear sender identification and unsubscribe options

Still Having Issues?

If you continue to experience blacklist-related delivery problems:

  1. Document everything: Keep records of all delisting requests and responses
  2. Consider dedicated IP: Explore dedicated IP options if available
  3. Review sending practices: Audit your entire email strategy for compliance issues