pin this page. when deliverability drops, start here.

quick diagnosis

Symptom Likely Cause Go To
Emails going straight to spam on fresh domains DNS misconfiguration Chapter 1
Open rates dropped suddenly (within 1-2 days) Sender reputation damage Chapter 2
Open rates declining gradually over 2-4 weeks Silent throttling Chapter 3
Domains burning every 2-3 weeks Skipped warmup + aggressive volume Chapter 2
Delivery reports normal but zero replies Silent throttling Chapter 3
Blacklist notification Reputation damage (severe) Chapter 2
Mixed placement (some Primary, some Spam) Throttling or DNS inconsistency Chapter 1, then 3

DNS quick check (per domain)

reputation recovery timeline

Severity Signs Recovery
Minor Promotions tab, slight open drop 5-7 days
Moderate Spam placement, sub-10% opens 14-21 days
Severe 90%+ spam, blacklisted 30+ days or rotate

throttling response (immediate)

  1. cut volume by 40-50%
  2. increase warmup ratio
  3. diversify templates (rewrite, don't just swap variables)
  4. stagger sends across 6-8 hours
  5. monitor 7-10 days before scaling back up

daily monitoring targets

Metric Healthy Watch Urgent
Open rate 25%+ 15-25% below 15%
Reply rate 3%+ 1-3% below 1%
Bounce rate below 2% 2-3% above 3%
Spam complaints 0 1-2 3+
Warmup open rate 40%+ 30-40% below 30%

tools referenced in this guide