Guides and playbooks. The long reads.
In-depth guides on email deliverability, cold outreach and AI personalization, written for founders and operators who run outbound themselves.
Email deliverability in 2026: rule updates and the complete technical guide
Authentication mandates, AI filtering, warmup strategy, and the infrastructure non-negotiables. A complete technical guide for founders and operators running outbound.
How to start cold email outreach in 2026: a founder's playbook
Domain setup, warmup, list building, copy that beats AI filters, and the stack you actually need, in the order that matters.
AI email personalization: how to lift B2B reply rates
The conversion math, the four levels of personalization, why generic intro lines stopped working, and the deliverability constraint that gates it all.
Cold email deliverability, measured
Where cold email lands by provider and domain age, the receivers' 2026 rules, infrastructure, warmup, content, list and monitoring.
How many cold emails per day?
The providers' caps in their words, the safe volume by domain age, the days a mailbox takes to earn it, and how many mailboxes you need.
Emails going to spam all of a sudden
The six things that change in the week before a drop, how to confirm each in minutes, and what recovery takes.
Google Postmaster domain reputation
The four tiers in Google's words, why a dashboard shows no data, the study of connected domains, and the recovery steps in order.
Gmail & Yahoo bulk sender requirements
The rules in each provider's own words, dated and linked, the enforcement timeline, the rejection codes, and a checker.
Microsoft bulk sender requirements
SPF, DKIM and aligned DMARC for 5,000 a day to Outlook.com, the 5.7.515 rejection, SNDS and JMRP, and a checker.
Emails going to the Promotions tab
What the tab is in Google's words, how to test for it, when to fight it, annotations for the senders who belong there, and the seed-list fix.
Newsletter deliverability
Where newsletters land by provider, the receivers' rules for bulk mail, the list and the domain, and the seed-list fix on a live issue.
Are pre-warmed domains worth it?
What is sold, what transfers with a domain or an account, Google's rules, what happens to bought accounts, and the 21 days you own.
What is an email seed list?
Real mailboxes added to a send that report where it landed per provider, and with MailStrike's seeds, act on it.
Read enough? See where your mail lands today.
A Free Deliverability Test shows inbox, promotions, or spam per provider, with what to fix first. Or book a demo and we connect a mailbox live.