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ColdMail
Guide

Complete Deliverability Guide

by Clara Monroe

Everything you need to avoid spam.

DNS Authentication Setup

SPF Record

Add this TXT record to your DNS:

v=spf1 include:_spf.google.com ~all

DKIM Record

Generate DKIM key in your email provider and add the TXT record:

selector._domainkey.yourdomain.com IN TXT "v=DKIM1; k=rsa; p=YOUR_PUBLIC_KEY"

DMARC Record

Add this TXT record to your DNS:

v=DMARC1; p=quarantine; rua=mailto:dmarc@yourdomain.com

Domain Warmup Process

Week 1-2: Foundation

  • Start with 20-50 emails per day
  • Send to internal contacts and engaged prospects
  • Focus on high-quality content and personalization
  • Monitor bounce rates and engagement metrics

Week 3-4: Growth

  • Increase volume by 20-30% weekly
  • Expand to verified prospect lists
  • Continue monitoring deliverability metrics
  • Implement engagement-based segmentation

Week 5+: Scale

  • Reach target sending volume
  • Implement advanced automation
  • Optimize based on performance data
  • Maintain consistent quality and monitoring

Sending Best Practices

Content Guidelines

  • Keep emails under 150 words
  • Use clear, professional language
  • Avoid spam triggers and excessive formatting
  • Include clear call-to-action
  • Personalize based on research

Sending Patterns

  • Vary send times across time zones
  • Avoid peak spam filter hours
  • Distribute volume across multiple inboxes
  • Implement engagement-based throttling
  • Monitor real-time metrics and adjust

Monitoring & Maintenance

Weekly Tasks

  • Check bounce rates, complaint rates, and blocklist status
  • Review postmaster tools (Gmail, Outlook, Yahoo)
  • Analyze engagement trends and adjust volume accordingly
  • Monitor authentication status and DNS records

Monthly Tasks

  • Clean email lists and remove inactive contacts
  • Update authentication records if needed
  • Review and optimize sending patterns
  • Analyze reputation trends and warmup strategies
  • Update compliance and privacy policies

Troubleshooting Common Issues

High Bounce Rate (>5%)

Usually indicates poor list quality or domain reputation issues.

  • Verify email addresses before sending
  • Check domain reputation on SenderScore or similar tools
  • Reduce sending volume temporarily
  • Review and clean your contact list

Low Open Rate (<10%)

Often caused by poor subject lines or landing in spam folders.

  • Test subject lines with A/B testing
  • Check spam folder placement
  • Improve sender name and email address
  • Review content for spam triggers

Domain Blocklisting

Immediate action required to restore deliverability.

  • Check blocklist status on major services (Spamhaus, Barracuda, etc.)
  • Submit removal requests with evidence of compliance
  • Implement stricter sending practices
  • Consider using a new domain if reputation is severely damaged