How we accidentally tanked our primary domain's email deliverability

Hey everyone, I wanted to share a quick post-mortem on an infrastructure mistake that almost cost us our entire outbound sales funnel last month.

We imported a legacy event list without validating it first, causing our hard bounce rate to shoot past 5%. Within 48 hours, Gmail and Outlook throttled our domain entirely.

What we learned during the recovery process:

• Standard apology forms to postmasters don't work unless you prove your sending behavior has changed.

• We had to implement a strict 14-day email blackout across marketing, sales, and transaction systems.

• We moved our newsletters to an isolated subdomain (news.ourbrand.com) to keep our main root domain protected.

If you're noticing an unexpected drop in your open rates, don't wait for a complete block. Run a quick check through a domain blacklist checker to see if your server IP has been flagged.

You can read the full step-by-step technical breakdown here: blacklisted email domain recovery guide