Symptoms#
- Messages landing in spam despite previously good placement
- Bounces mentioning policy, authentication, or reputation
- Provider dashboards showing a drop in reputation or authentication pass rate
Diagnosis steps#
- Confirm the configuration is live: query DNS from an external resolver and check the sending platform's settings page.
- Send to a seed mailbox and read the full headers, especially Authentication-Results.
- Compare the domains in From, Return-Path, and DKIM d= for alignment.
- Check provider dashboards (Google Postmaster Tools, Microsoft SNDS) for reputation and error rates.
- Review recent changes: new vendors, DNS edits, list imports, volume spikes.
Likely causes#
- Reporting opens as success when Apple inflates them by prefetching.
- Ignoring the complaint rate until Postmaster Tools flags it.
Fix and re-verify#
- Track clicks and replies as primary metrics; opens are unreliable after Mail Privacy Protection.
- Set benchmarks per segment and channel rather than industry averages.
- Watch unsubscribe rate (aim under 0.5%) and complaint rate (under 0.1%).
- Feed engagement back into segmentation and sunset policies.
Frequently asked questions#
What is a good click-through rate?
2 to 5% for marketing email is common; transactional mail often exceeds 10%.