A friend of mine recently hit a wall: every email he sent was suddenly landing in spam.
He finally looked at his recent sign-ups and found the problem: a massive influx of low-quality traffic from a specific region. He decided to block the entire country, and just like that—full recovery.
Now, blocking a whole country is a nuclear option (and probably not one you want to take). But the lesson holds up: even a small stream of garbage sign-ups can poison your reputation.
I strongly recommend spending 5-10 minutes today to audit your sign-ups. If you find a stream of low quality sign-ups, it can compound to a large % of your email traffic—enough to spam box you.
The Silent Killer of Deliverability
You think you have a deliverability problem. Maybe your content is too salesy? Maybe you're sending too many emails?
But often, the problem isn't what you're sending. It's who you're sending it to.
In my friend's case, he was getting hammered by low-quality traffic. These weren't necessarily malicious hackers trying to break in. They might have been bot farms, click farms, or just users looking for a freebie with zero intent to engage.
When you send emails to these addresses, two things happen:
- Bounces: The emails don't exist.
- Zero Engagement: The emails exist, but nobody opens them.
ISPs like Gmail and Outlook see this. They see you sending 1,000 emails and getting 5 opens. They assume you're spamming, and they downgrade your reputation. Suddenly, your legitimate customers—the ones who actually want to hear from you—can't find your emails.
The Nuclear Option: Geo-Blocking
My friend chose the "nuclear" option: Block the entire region.
And it worked! His deliverability recovered.
But this is a blunt instrument. What if you have legitimate customers in that region? What if the next wave of spam comes from Brazil, or Russia, or a VPN in Ohio?
You can't play "Whack-a-Mole" with countries. You need a smarter filter.
The Scalable Fix: Real-Time Verification
Instead of blocking entire continents, you should block the type of user that causes problems.
Most low-quality signups share common traits:
- Disposable Domains: They use temporary email services like
10minutemail.comorguerrillamail.com. - Invalid MX Records: The domain doesn't even have a mail server.
- Gibberish: The username is
asdf12345.
You can catch these at the front door.
By implementing real-time email verification on your signup form, you can reject these users before they ever enter your database. You don't need to block a whole country. You just need to block [email protected], whether they are in Mumbai or Manhattan.
Automate the Audit
If you're seeing a dip in open rates, go look at your last 100 signups. Do they look real?
If you see a pattern of junk, it's time to put a guard at the gate.
Our API is designed to be that guard. We maintain a constantly updated list of disposable domains and perform real-time checks to ensure every email you collect is valid and deliverable.
Pro Tip: You don't have to throw them away. If a user tries to sign up with a disposable email, just show a friendly error: "Please use your work email." You'd be surprised how many "bots" turn into real humans when you ask nicely.
Don't let bad data kill your good emails. Audit your list, block the junk, and get back to the inbox.