Why warmup emails aren’t arriving in my inbox

If warmup has been running for days and nothing has arrived, there are four realistic explanations, and only one of them clears by itself. By far the most common is that the domain is not set up to accept email — mail addressed to it has nowhere to be delivered, so it never lands anywhere, no matter how many times it is sent. The second is that a filter or a rule is moving warmup mail out of the inbox after it arrives. The third is an address that can send but has no inbox behind it. The fourth is different in kind from the other three: the mail is arriving perfectly well, but we have not been given permission to read the inbox, so we cannot see it — which happens when a Microsoft 365 or Google Workspace administrator has allowed sending and blocked reading. All four are fixable, all four are fixed on your side, and the two-minute check below tells you which one you are looking at. If the check passes cleanly and mail still is not arriving, then it is the passing kind and it really does sort itself out — but check first, because waiting on a problem that will not clear costs you weeks.

WarmySender runs your outreach on autopilot with AI agents, across Cold Email, Email Warmup, LinkedIn, Instagram and Multichannel sequences — plus real-time email verification. This guide covers an Email Warmup question: what to do when warmup is running and nothing is arriving at your address.

The two-minute check, before anything else

Do this first. It separates a problem you must fix from one that clears on its own, and it takes about two minutes.

1. Send the address an email from somewhere else. Use a personal account on a different provider — not another address on the same domain, which can be delivered internally without ever leaving the building and so proves nothing. Write anything. Send it.
2. Wait five minutes and look. Check the inbox, and then check the spam or junk folder, and then check any other folder your mail app shows.
3. Read the answer. If the test email never turns up anywhere — or comes straight back as undelivered — the address cannot receive mail at all, and warmup was never going to arrive either. Start with the next section. If it turns up in spam or in some other folder rather than the inbox, skip to the filter section. If it lands in the inbox within a minute or two, mail is being delivered fine, and there are two possibilities left: either we are not allowed to read the inbox (see the fourth cause — the giveaway is a flat zero arriving, day after day, on a mailbox managed by an organisation), or the receiving side is healthy and you are looking at the passing kind of quiet, covered in Warmup shows active but no emails are arriving.

One thing worth saying plainly: warmup emails are ordinary emails. They travel the same way as the test you just sent and land in the same places. There is nothing special about them that could make them arrive when a normal email cannot.

Why does my address have to be able to receive email?

Because warmup is not a simulation. It is real inboxes exchanging real email. Your address sends friendly, genuine messages to other real inboxes, and other real inboxes send messages back to yours. Both halves are what make the account look, to a mailbox provider, like a healthy one that people are genuinely pleased to hear from — and that is the reputation warmup is building for you.

So a warmup address has a job most sending tools never ask of it: it has to be able to receive. An address that only sends is fine for a mail-merge and useless for warmup, because the incoming half simply never happens. That is the trap this page exists to explain, and it catches good, careful people all the time.

The most common cause: your domain isn’t set up to accept email

Every domain carries a small public setting that tells the rest of the internet where email for that domain should be delivered. It is the postal-redirection card of the internet: without it, mail addressed to anyone@yourdomain.com has no destination, so it is not delayed or filtered or put in spam — it is simply turned away. Nothing you do inside WarmySender can change that, because the decision happens before any message reaches your side at all.

This setting is usually called the MX record, and it lives with whoever manages your domain’s settings — normally the company you bought the domain from, or whoever you use to manage its DNS. If you have set up mail for the domain with a mailbox provider, that provider gave you the exact values to enter. If nobody ever entered them, the domain has no way to receive mail, and it never has had.

The trap: a domain can send email perfectly well and still have nowhere to receive it

This is the part that catches people, and it is completely reasonable to be caught by it. Sending and receiving are two separate arrangements. You can buy a domain, point it at a sending service, and start sending campaigns that land beautifully — while that same domain has never been set up to receive a single message. Everything looks right. Mail goes out. Nobody tells you that replies, warmup, and anything else addressed to you are being turned away, because from the sending side there is nothing to see.

It is worth fixing even if you never intended to read mail at that address, for two reasons that have nothing to do with warmup. Replies from real prospects are being turned away too — the interested ones, the ones you paid to find. And a domain that cannot receive mail is a well-known signal to mailbox providers that a sender is not a real business, which works against the reputation you are building.

A brand-new domain is the usual version of this

If the domain was bought recently, the most likely story is simply that its mail settings were never finished, or were entered in the last day or two and have not taken effect everywhere yet. Changes to a domain’s settings spread across the internet gradually, so give it a few hours after saving them before you judge the result — and then re-run the two-minute check above rather than assuming.

How do I check whether my domain can accept email?

Two ways, and they answer slightly different questions. Do both if you can.

1. The test email from the two-minute check above. This is the real-world answer: it either arrives or it does not.
2. A free MX lookup. Search the web for MX lookup and open any of the free checkers that come up — you do not need an account and there is nothing to install. Type in your domain (just yourdomain.com, no @ and no mailbox name) and read what comes back. If it lists one or more mail servers, the domain is set up to receive. If it comes back empty, or says no records were found, that is your answer: email sent to that domain currently has nowhere to go.

Check every domain you have connected, not just the one you had in mind. Where this goes badly wrong is when several domains are connected at once and only some of them are set up — the working ones make everything look fine on the dashboard while the others quietly receive nothing.

Where do I fix it?

Wherever your domain’s settings are managed — the company you bought the domain from, or the service you use to manage its DNS. Sign in there and look for a section called DNS, DNS records, or similar. The values you need come from whoever hosts your mailboxes: if you use a business email provider, their setup guide lists the exact entries to add, and it is usually a matter of copying two or three lines. If your mailboxes are with a web host, their support pages will have the same thing.

If you are not sure who manages your domain or who hosts the mailboxes, the person who set the domain up will know, and so will your web host’s support team. This is a routine request and they answer it every day.

What happens after I fix it?

Give it a few hours to take effect, then send yourself another test email from an outside account. Once that arrives in the inbox, incoming warmup can start reaching you as well. Nothing needs to be reconnected and nothing needs to be switched off and on — and please do not remove and re-add the mailbox, because that throws away the warmup history it has already built. Leave warmup running while you sort the domain out; the sending half has been working the whole time.

Second cause: a filter or rule is moving warmup email out of the inbox

If your test email arrived but landed somewhere other than the inbox, this is your answer. Warmup mail has to reach the main inbox to count. Anything that quietly sweeps it into a folder, archives it, or marks it as read on arrival takes it out of the picture — and it will look to you exactly like nothing arrived, because as far as your inbox is concerned, nothing did.

The commonest version of this is a rule the customer made themselves, usually for a perfectly sensible reason. Warmup mail is tidy but it is not interesting to read, so people set up a rule to file it away and then forget the rule exists. One customer hit precisely this, found the rule herself, and everything came back the moment she removed it. If you tidied warmup mail away at some point, that is the first place to look.

Where to look

• Your rules and filters. In Gmail, open Settings and then Filters and Blocked Addresses. In Outlook or Microsoft 365, open Settings, then Mail, then Rules. Other apps have the same thing under Rules, Filters, or Message handling. Look for anything matching on a subject tag, on a sender, or on words that would catch warmup mail, and check where it is sending them.
• Spam and junk. If warmup is landing there, mark a few of the messages as not spam. That is a signal in its own right and it helps.
• Blocked senders. Check that nothing sweeping has been added to a blocked or safe-sender list.
• Tabs and categories. Gmail’s Promotions and Updates tabs are not the inbox for this purpose. If warmup is landing in one of them, drag a message into the Primary tab.
• Anything sitting in front of the mailbox. Some domains run mail through an extra security or filtering product before it reaches the inbox. If yours does, its quarantine is worth a look too.

There is a related point that surprises people: seeing warmup mail in your inbox is normal and expected, and it is not a fault. That is covered in Why warmup emails appear in your inbox, which also explains the tidying that does happen and why the subject tag is there.

Third cause: the address can send, but there is no inbox behind it

The last one is quieter, and it usually turns up on an address that was created purely to send from — something like noreply@, or an address set up on a sending service without a real mailbox attached to it. The domain may be set up to receive mail perfectly well; it is this particular address that has nowhere to put it.

The check is the same test email, sent to that exact address. If mail to [email protected] arrives but mail to [email protected] does not, the domain is fine and the address is the problem. The fix is to give it a real mailbox, or to run warmup on an address that already has one. An address with no inbox can never complete the receiving half of warmup, and connecting it again will not change that.

Fourth cause: the mail is arriving, but we are not allowed to read the inbox

This one is different in kind from the three above, and it is the reason this section exists at all. In the other three, mail is genuinely not reaching the inbox. Here it is reaching the inbox, perfectly and on time — we simply have no permission to look, so we cannot count any of it, and the page reports nothing arriving.

It happens on mailboxes managed by an organisation, meaning Microsoft 365 or Google Workspace. On those, sending and reading are two separate permissions, and an administrator grants each one independently. It is common to find sending switched on and reading switched off, because they are two different tick-boxes sitting side by side and only one of them is ever mentioned when a mailbox is set up. When that is the shape of it, your mailbox sends warmup and campaign mail exactly as normal — which is why everything else looks healthy — and none of what arrives can be seen.

Two signs point at it. The arrivals figure sits at a flat zero, day after day, rather than being merely low; an address with an ordinary receiving problem usually gets something eventually. And the test email above lands in the inbox normally when you look in the mailbox's own webmail, while WarmySender still shows nothing. If both of those are true, this is your cause.

The fix is one tick-box in your administrator's console and it takes about a minute. The exact click-path for Microsoft 365 and for Google Workspace, how to do it for several mailboxes at once, and what to expect afterwards are all in Why can’t WarmySender read my inbox? — that page is written to be forwarded straight to whoever administers your email.

What does WarmySender show when it spots this, and what should I do next?

When we can see that mail sent to one of your addresses is being turned away rather than delivered, we say so on that mailbox instead of leaving it looking healthy, and we link here. We do not fix it silently, because we cannot: the setting that has to change is on your domain, and only you or whoever manages it can change it. What we can do — and now do — is stop other inboxes sending warmup into an address that has nowhere to receive it, so the attempts do not pile up while the real problem goes unnoticed.

The other two notes you may see on a mailbox mean different things, and it is worth knowing which one you have:

• Not receiving warmup — that inbox has simply not received warmup for a few days and we are trying again. It is the passing kind. Full explanation: Warmup shows active but no emails are arriving.
• Incoming warmup paused — we deliberately stopped other inboxes sending warmup to that address, because mail sent there did not get through. It either carries a restart date or holds until our team reviews the address. Full explanation: Why is incoming warmup paused on my inbox?
• We can’t sign in to check this inbox — mail is arriving fine, but we have not been given permission to look at it, so none of it can be counted. Your sending is unaffected. This is the fourth cause above, and it is fixed by an administrator rather than by you. Full explanation and the exact admin steps: Why can’t WarmySender read my inbox?

And if there is no note at all but nothing is arriving, do not wait for one. Run the two-minute check. It costs less than a day of waiting and it answers the question outright.

What not to do

• Do not disconnect and reconnect the mailbox. It loses the warmup history that address has already built, and it changes nothing about whether mail can be delivered to it.
• Do not switch warmup off and on. The sending half is working; there is nothing to reset.
• Do not change your warmup settings. Volume, schedule and ramp all describe sending. None of them touch the receiving side.
• Do not wait it out without checking. This is the one that costs real time. If the domain cannot receive mail, waiting another week produces another week of nothing.

Frequently asked questions

Warmup has been running for a week and nothing has arrived. What is wrong?

Most likely the domain is not set up to accept email, which means mail addressed to it has nowhere to be delivered and is turned away before it reaches you. The quickest way to find out is to send that address an email from a personal account on a different provider and see whether it arrives. If it does not turn up anywhere, that is your answer and the fix is on your domain rather than in WarmySender. If it arrives in the inbox within a couple of minutes, the receiving side is healthy and you are probably looking at a passing quiet spell instead.

What is an MX record, in plain English?

It is a small public setting on your domain that tells the rest of the internet where email for that domain should be delivered. Think of it as a postal-redirection card: without it, mail addressed to anyone at your domain has no destination at all, so it is not delayed or filtered, it is simply turned away. It lives with whoever manages your domain's settings, normally the company you bought the domain from or whoever manages its DNS, and the values to enter come from whoever hosts your mailboxes.

My campaigns send fine, so how can my domain not accept email?

Because sending and receiving are two separate arrangements, and having one does not give you the other. You can point a domain at a sending service and send campaigns that land beautifully while that same domain has never been set up to receive a single message. Nothing warns you, because from the sending side there is nothing to see. It is worth fixing even if you never planned to read mail at that address: replies from real prospects are being turned away too, and a domain that cannot receive mail looks to mailbox providers like a sender that is not a real business.

How do I check whether my domain can receive email?

Two ways, and they answer slightly different questions. Send a test email to the address from a personal account on a different provider — not from another address on the same domain, which can be delivered internally and proves nothing — and see whether it arrives. And search the web for "MX lookup", open any of the free checkers, and type in your domain on its own, with no @ and no mailbox name. If the checker lists one or more mail servers, the domain is set up to receive. If it comes back empty or says no records were found, email sent to that domain currently has nowhere to go.

Where do I fix it, and how long does it take?

Wherever your domain's settings are managed — the company you bought the domain from, or the service you use to manage its DNS. Sign in and find the section called DNS or DNS records. The exact values come from whoever hosts your mailboxes; a business email provider's setup guide lists them, and it is usually two or three lines to copy. After saving, give it a few hours to take effect, then send yourself another test email. Once that arrives in the inbox, incoming warmup can reach you as well.

Everything arrives except warmup. Could a filter be doing this?

Yes, and it is the second most common cause. Warmup mail has to reach the main inbox to count, so any rule that files it into a folder, archives it, or marks it as read on arrival takes it out of the picture and makes it look as though nothing arrived. Very often it is a rule the customer set up themselves to tidy warmup mail away and then forgot about. Check your rules and filters — in Gmail, Settings and then Filters and Blocked Addresses; in Outlook or Microsoft 365, Settings, then Mail, then Rules — and also check spam or junk, your blocked-senders list, and Gmail's Promotions and Updates tabs.

Will this fix itself if I wait?

Only one of the four causes does. A short quiet spell on a healthy address really does clear by itself within a few days. A domain that is not set up to accept email will not, a filter moving warmup out of the inbox will not, an address with no mailbox behind it will not, and a mailbox we have not been given permission to read will not — those four stay exactly as they are until somebody changes them, and no amount of retrying on our side makes a difference. That is why the two-minute check comes first: waiting is the right answer for one case and an expensive mistake for the other four.

My test email arrives fine, but WarmySender still shows nothing. What now?

That combination points at a permissions problem rather than a delivery problem: the mail is reaching the inbox, but we have not been given permission to read it, so we cannot count any of it. It happens on mailboxes managed by an organisation on Microsoft 365 or Google Workspace, where sending and reading are two separate permissions and an administrator can allow one and block the other. The other giveaway is that the arrivals figure sits at a flat zero day after day, rather than being merely low. Your sending is completely unaffected the whole time. The fix is a single tick-box in your administrator's console and takes about a minute — the exact steps for both providers are in "Why can't WarmySender read my inbox?".

Can WarmySender fix my domain settings for me?

No, and we would not want to be able to. The setting lives on your domain, with whoever manages it, and only you or that person can change it. What we do instead is tell you when we can see that mail sent to an address is being turned away rather than delivered, so the mailbox stops looking healthy while nothing arrives, and stop other inboxes sending warmup into an address that has nowhere to receive it. The change itself is a few minutes' work at your domain provider, and their support team does it every day.

The address was only ever meant for sending. Does that matter?

For warmup, yes. Warmup is real inboxes exchanging real email, so the address has to be able to receive as well as send — an address created purely to send from, with no mailbox behind it, can never complete the receiving half. If mail to one address on the domain arrives but mail to this one does not, the domain is fine and the address is the problem. Give it a real mailbox, or run warmup on an address that already has one. Reconnecting it will not change anything.

Should I disconnect and reconnect the mailbox while I sort this out?

No. Disconnecting loses the warmup history that address has already built, which is real progress measured in weeks, and it does not change whether mail can be delivered to the address. The same goes for switching warmup off and on or changing your warmup settings — those all describe sending, and the sending half has been working the whole time. Leave warmup running, fix the receiving side, and the incoming half picks up once mail can reach you.

I have several domains connected. Do I need to check all of them?

Yes, check every one. This is where it goes most badly wrong: when several domains are connected at once and only some of them are set up to receive, the working ones make the dashboard look fine while the others quietly receive nothing. Run the MX lookup for each domain separately, and send a test email to at least one address on each. It takes a couple of minutes per domain and it is the difference between finding this today and finding it in a month.

I checked everything and mail still is not arriving. What now?

Then we would like to look at it with you. Email us the address, and tell us two things: what happened to the test email you sent from an outside account, and what the MX lookup showed for that domain. Those two answers rule out most of the ground on their own and let us start from the right place rather than asking you to repeat the checks you have already done.

Related reading

• Warmup shows active but no emails are arriving — telling the passing kind of quiet apart from the kind you have to fix
• Why is incoming warmup paused on my inbox? — what the paused note means and how each kind ends
• My inbox rate looks great but I’m not receiving warmup emails — why the headline score measures sending, not receiving
• Why warmup emails appear in your inbox — why you see warmup mail, and the subject tag that lets you filter it
• Why is my mailbox full? — a full mailbox turns incoming mail away; how to spot it and clear it
• Why can’t WarmySender read my inbox? — when the mail arrives fine but an administrator has not allowed us to read it, and the exact steps to switch reading on
• Why does warmup need incoming access? — why we need to see the receiving side at all
• How email warmup ramps up — what to expect in your first hour, first day, and first week
• Your warmup page — per-mailbox status, including how much has arrived in the last seven days
• Full documentation — Cold Email, Email Warmup, LinkedIn, Instagram and Multichannel guides