What Is a Catch-All Email Address?
A catch-all domain accepts mail for every address, so verification cannot confirm a single mailbox. Here is what that means for your list and how to send safely.
Read explainerCatch-All Email Detection: How It Actually Works
How SMTP-level verification detects a catch-all (accept-all) domain, why the detection is probabilistic, and how to handle the addresses it flags.
Read explainerWhat Are Role-Based Email Addresses?
info@, support@ and sales@ belong to teams, not people. Learn when role addresses hurt deliverability and when they are perfectly fine to keep.
Read explainerWhat Are Spam Traps and How Do You Avoid Them?
Pristine, recycled and typo spam traps quietly destroy sender reputation. Learn how they get onto lists and how verification and hygiene keep them out.
Read explainerHard Bounce vs Soft Bounce: What's the Difference?
Hard bounces are permanent failures you must suppress immediately. Soft bounces are temporary. Here is how to read bounce codes and act on them.
Read explainerWhat Is a Good Email Bounce Rate?
How to calculate bounce rate, what counts as healthy by industry, and the fastest ways to bring a high bounce rate back under control.
Read explainerHow SMTP Email Verification Works
A step-by-step look at the SMTP handshake email verifiers use to check whether a mailbox exists — without sending a message.
Read explainerWhat Are MX Records and Why Do They Matter for Email Verification?
MX records tell the internet where a domain's email should be delivered. Missing or misconfigured MX records guarantee a bounce.
Read explainerWhat Is Sender Reputation and How Do You Protect It?
Mailbox providers score every sending domain and IP. Learn the inputs to that score and the habits that keep you in the inbox.
Read explainerWhat Is Greylisting in Email?
Greylisting temporarily rejects unfamiliar senders to filter spam. It also makes email verification return 'unknown' — here is how to handle it.
Read explainerEmail List Hygiene: A Practical Maintenance Guide
A repeatable schedule for cleaning, segmenting and sunsetting contacts so your list stays deliverable as it grows.
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