Why am I not receiving emails? Here’s how I debug it step by step.

This one’s for the folks staring at an empty inbox wondering, “Why the hell didn’t it land?”

Whether you're testing your own sends or a client is blowing up your Slack saying their welcome emails aren’t coming through, it’s one of those deceptively frustrating issues that can burn hours unless you get methodical about it.

I’ve pulled my hair out because of this more than once, so I just wanted to show you how I troubleshoot missing emails, both as a sender and a recipient. This might not work for everyone, but I hope it’ll at least help you find the pattern in the chaos.

First things first: who’s not receiving what?

There’s a big difference between:

• A specific person not receiving a message (e.g., your Gmail test account)
• You not receiving test emails from your ESP
• None of your subscribers receiving anything
• The email arriving, but in spam/promotions
• The email never leaving your ESP or server at all

Most people lump all of this under “email didn’t arrive,” but the context narrows the problem space.

Scenario 1: Your ESP says the email was sent, but nothing shows up

This is the classic ghosted email. No bounce, delivery confirmation, or even an error.

Start here:

Check the sending domain’s DNS records: SPF, DKIM, and DMARC.

Missing or misconfigured records are still one of the most common culprits, especially for new subdomains or freshly set up email platforms. Grab something like MxToolbox or Google Admin Toolbox to verify.

Review suppression lists

Most ESPs will suppress emails to contacts who previously bounced, reported for spam, or unsubscribed, and not tell you unless you go looking. It’s especially sneaky if you’re testing using the same email over and over again.

Look in the promotions or spam folder

This sounds obvious, but there’s no shortage of marketers who overlook it. Gmail in particular is a black box because even perfectly configured domains can land in promo or spam for reasons ranging from fishy formatting to overuse of images to bad neighbor IPs.

Try a different inbox provider

Send to multiple test addresses (Gmail, Outlook, Yahoo). If it shows up in Yahoo but not Gmail, that could be a telling sign. Not conclusive, but at least directional.

Scenario 2: It’s not just you; the email isn’t reaching anyone

If zero emails are reaching the list (and it’s not user error), this is when I start to sweat, but also when I get systematic.

Send a plain-text test email to a small seed list

Take out all formatting, links, and images. Just say “test” or something minimal. If this delivers, the issue is likely content-related (or triggered by something in your HTML or CTAs).

Check your warm-up history

If you’re sending from a new domain or recently ramped up volume, mailbox providers might still be skeptical. This is where I’d recommend a service like InboxAlly. Not because you have to use it (you don’t), but because I’ve used it multiple times now to recover inbox placement and preempt damage when changing infrastructure.

Their system mimics natural email behavior using real inboxes like open, read, reply, archive, etc. It’s helped me rebuild my reputation with Gmail and get out of the promotions tab more than once.

Use Gmail Postmaster Tools or SNDS

If your domain is marked as “Low” in GPT, you’re fighting an uphill battle. Inbox placement depends on domain reputation, IP rep, complaint rate, and engagement. Google gives you just enough data to see when you’ve got a problem (but not always why).

Scenario 3: The email is being sent, but intermittently received

This one is tricky and often points to infrastructure or throttling.

Check throttling limits or ESP queue delays

Some providers will delay delivery to protect their reputation, especially if your list has a history of bounces or you’re sending big blasts. The email might be delayed, not missing.

Are you using a shared IP?

If yes, someone else’s bad behavior might be dragging you down. Some inboxes will filter or drop shared IPs with inconsistent sending history. Moving to a dedicated IP isn’t always a silver bullet, but if you have the volume, it’s worth testing.

Scenario 4: You’re not receiving test emails sent to yourself

Weirdly, this happens more often than you’d expect and is usually your inbox, not the email.

Internal filters are brutal

Company inboxes, in particular, will often flag or drop marketing-style messages before they get to spam. Even Gmail will sometimes not show your own test email if you send it to yourself using the same account.

Workaround: Send test messages to a different inbox, or add a rule that always shows “from me” messages.

Test platforms are your friend

Mail-Tester[dot]com or GlockApps can give you clues on where your email is landing, which filters you’re triggering, and what your header setup looks like. Not perfect, but helpful for early diagnosis.

Other things I’ve seen break deliverability for no obvious reason:

• Broken unsubscribe links
• Too many images (or all-image emails)
• Suddenly changing sending cadence
• Email templates with legacy HTML
• Domain forwarding setups that mess with DNS

TL;DR if you’re just skimming this:

If your emails aren’t being received, your job is to eliminate possibilities one by one. Start with technical setup, move to reputation, and then consider content and list health. And if you’re still fixing things on your own, a warm-up and engagement tool like InboxAlly can save a launch or get you unstuck faster than trial-and-error.

Hope this helps someone. Curious to hear your own weirdest “where did my email go?” stories or what worked when nothing else did.