TABLE OF CONTENTS

Recipient Policy Block Resolution Guide

What's Happening?

Your emails are being rejected by recipient mail servers due to administrative policies, security restrictions, or access control rules. Unlike technical delivery failures, these blocks are intentional policy decisions by the receiving organization to protect their email environment from unwanted or potentially harmful messages.

Quick Diagnosis: Identifying Policy Blocks

Common Policy Block Messages

  • "The recipient's mail server has blocked the message due to administrative or policy restrictions"
  • "The recipient's mail server rejected the message due to its policies, such as user unknown, relay denied, or spam detection"
  • "The recipient's mailbox only accepts mail from approved senders; your address is not authorized"
  • "The recipient's mail server rejected the sender due to policy or blocklist rules"
  • "The recipient's domain is actively rejecting mail due to its own policies"
  • "The recipient's organization blocks external email forwarding for security or policy reasons"
  • "The recipient has unsubscribed or opted out, so email delivery is blocked by policy"
  • "Sender is not allowed to email this group due to group membership or external sender restrictions"
  • "The recipient's mail server rejected the message due to strict connector policies restricting allowed IPs or certificates"

Understanding Recipient Policy Blocks

Key Concepts

Important Information:

  • Policy blocks are intentional restrictions, not technical failures
  • These blocks protect organizations from spam, phishing, and unwanted communications
  • Resolution often requires action from both sender and recipient sides
  • Some policy blocks are permanent organizational decisions

Policy Block Categories

Sender-Based Blocks:

  • IP address or domain blacklisting
  • Sender reputation restrictions
  • Unauthenticated sender policies

Content-Based Blocks:

  • Spam filter triggers
  • Content policy violations
  • Attachment restrictions

Access Control Blocks:

  • Whitelist-only policies
  • External sender restrictions
  • Group membership requirements

Step-by-Step Policy Block Resolution

Step 1: Verify Email Authentication

Check your domain authentication setup:

  1. Navigate to authentication settings:
    • Go to Settings → Email Services → Sending Domain & IP
    • Verify SPF, DKIM, and DMARC records are properly configured
    • Ensure all authentication checks show "Verified" status
  2. Test authentication externally:
    • Use MXToolbox.com to verify SPF and DKIM records
    • Check DMARC policy alignment using dmarcian.com

Authentication Success Indicators

  • All domain verification checks pass in our platform
  • External tools confirm proper SPF, DKIM, and DMARC setup
  • No authentication-related bounce messages

Step 2: Monitor Sender Reputation

Assess your sending reputation:

  1. Check reputation scores:
    • Visit senderscore.org to check your IP reputation (aim for 80+)
    • Use Talos Intelligence to verify domain reputation
    • Check Microsoft SNDS if sending to Outlook/Hotmail users
  2. Review metrics:
    • Go to Marketing → Email Marketing → Analytics
    • Monitor bounce rates, spam complaints, and unsubscribe rates
    • Identify patterns in policy block messages

Step 3: Contact Recipient Organization

Reach out for whitelist consideration:

  1. Identify the right contact:
    • Look for IT administrator or email security team contacts
    • Check the organization's website for email delivery inquiries
    • Use alternative communication channels (phone, SMS)
  2. Prepare whitelist request:
    • Include your sending domain and IP addresses
    • Explain the business relationship and email purpose
    • Provide evidence of proper authentication and compliance

Step 4: Optimize Email Content and Practices

Reduce policy trigger likelihood:

  1. Review email content:
    • Avoid spam trigger words and excessive promotional language
    • Ensure proper text-to-image ratios
    • Include clear unsubscribe mechanisms
  2. Implement list hygiene:
    • Regularly clean bounced and unsubscribed contacts
    • Segment lists based on engagement levels

Content Optimization Success

  • Reduced spam score when tested through mail-tester.com
  • Improved engagement rates and fewer complaints
  • Consistent delivery to previously blocking domains

Recovery Timeline and Expectations

Phase 1: Immediate Actions (1-3 days)

  • Authentication fixes: Immediate improvement for authentication-based blocks
  • Expected outcome: Resolution of technical authentication issues

Phase 2: Reputation Building (2-4 weeks)

  • Consistent good practices: Gradual improvement in sender reputation
  • Expected outcome: Reduced policy blocks from reputation-based filters

Phase 3: Relationship Building (Ongoing)

  • Whitelist requests: Variable timeline depending on organization responsiveness
  • Expected outcome: Permanent resolution for specific recipient domains

Prevention Strategies

Proactive Monitoring

  • Weekly reputation checks: Monitor Sender Score and domain reputation
  • Bounce analysis: Review bounce messages weekly in analytics
  • Engagement tracking: Monitor open rates, click rates, and complaints

Email Best Practices

  • Permission-based lists: Only email contacts who have explicitly opted in
  • Regular list cleaning: Remove inactive and bouncing contacts monthly
  • Gradual volume increases: Slowly ramp up sending volumes to new domains
  • Consistent sending patterns: Maintain regular sending schedules and volumes

Still Having Issues?

If you continue to experience policy block challenges:

  1. Document patterns: Keep detailed records of which domains are blocking and specific error messages
  2. Consider alternative channels: Use phone, direct mail, or social media for critical communications
  3. Evaluate email strategy: Review whether your current approach aligns with recipient expectations