Insights on email privacy & productivity.
Tips, guides, and deep dives from the Cleanbox team.
Why We Built Custom Spam Symbols: Filling the Gap Between Score and Context
Rspamd is excellent at scoring email. But it does not know which senders your community trusts or distrusts. Our custom CLEANBOX_* symbols bridge that gap with crowd-sourced intelligence.
Cold Email Is Spam: Why Unsolicited Outreach Hurts Everyone
That personalized sales pitch in your inbox? Still spam. Why cold email damages the email ecosystem, how warmup services make it worse, and how to protect yourself.
How to Stop Promotional Emails Without Unsubscribing from Everything
You do not want to block every marketing email - just the noise. Here is how to keep the ones you want, silence the rest, and never see another subject line with "FLASH SALE" again.
How to Stop Getting Emails Without Unsubscribing
Sometimes clicking unsubscribe is not the right move. Here are alternative ways to stop unwanted email using filters, contact states, and aliases.
What Is Two-Factor Authentication and Why You Need It
Passwords alone are not enough to protect your accounts. Two-factor authentication adds a critical second layer of security - but not all 2FA methods are created equal. Learn how TOTP apps, hardware keys, and backup codes work, and why your email security is the foundation of it all.
Someone Signed Up for Services Using My Email Address - What to Do
Getting emails for accounts you never created? Here is why strangers use your email to sign up, how to stop it, and how to protect yourself.
Email for Side Projects: From Free to Professional in 10 Minutes
Your side project needs a professional email address. Here is the cheapest way to set it up - from domain purchase to receiving your first email.
Why We Built Relay: The Problem with Traditional MX Gateways
Traditional email gateways treat every address the same. Relay was designed from scratch with per-address control, SRS forwarding, and crowd-sourced reputation.
Email Encryption Explained: TLS vs PGP vs S/MIME
Three encryption technologies, three different problems solved. TLS encrypts the connection. PGP encrypts the message. S/MIME does both with certificates. Here is when you need which.
Why We Created Shield: Your Inbox Should Respect Your Schedule
You should decide when email arrives, how much of it, and from whom. Shield gives every alias its own rate limiter, delivery schedule, and sender approval list.
What Is an Email Header? A Beginner's Guide with Real Examples
You have seen "Show original" in Gmail but never clicked it. Here is what email headers are, what they reveal, and how to use them to verify a sender or diagnose a delivery problem - explained simply.
What Happens When You Click Unsubscribe: The Full Technical Story
List-Unsubscribe headers, one-click POST requests, tracking pixels, preference centers, and CAN-SPAM compliance - the surprisingly complex machinery behind the unsubscribe button.
