Why am I not receiving emails? How to troubleshoot

If you are not receiving emails, the cause is almost always one of five things: the message was filtered to spam or a rules folder, your mailbox is full, a forwarding rule is dropping it, your domain's MX records are wrong, or the sender's server is being blocked. Work from the mailbox outward — check the spam folder and storage first, then filters and forwarding, and only then move to DNS and blocklists. Most missing mail is recovered in the first two steps.

Quick Takeaways

• Check the spam or junk folder first — filtered mail is the single most common cause of "missing" email.
• A full mailbox silently rejects new mail; free up space or raise the quota before anything else.
• Inbox rules and server-side forwarding can move or delete messages before you ever see them.
• Broken or missing MX records mean senders have nowhere to deliver — verify them from outside your DNS panel.
• If one specific sender can't reach you, your server may be blocking their IP or a shared blocklist is.
• Greylisting delays first-time senders by design; the message usually arrives within an hour on retry.

Is the email in spam, junk, or another folder?

Start here, because filtered mail accounts for more "missing" email than every other cause combined. Open your Spam or Junk folder and search it for the sender. In Gmail, also check the Promotions and Updates tabs and search in:anywhere to include folders the main view hides. In Outlook, check Junk Email and the Other tab of the Focused Inbox.

If you find the message there, mark it "Not spam" or "Not junk" so the provider learns the sender is safe, and add the address to your contacts or a safe-sender list. A single message in spam is filtering; a pattern of a sender's mail landing in spam usually means that sender has an authentication or reputation problem on their end, not yours.

If a whole domain's mail is being filtered, ask the sender to confirm their SPF, DKIM, and DMARC are passing — misconfigured authentication is the most common reason legitimate mail gets junked.

Is your mailbox full or over quota?

A mailbox at its storage limit stops accepting new mail. Depending on the provider, the sender gets a bounce ("mailbox full" / "quota exceeded", often a 452 or 552 response) or the message is deferred and eventually returned. Either way, nothing reaches your inbox.

Check your account's storage usage. On Google Workspace and Microsoft 365 the quota is shared across mail, files, and photos, so a full Drive or OneDrive can block email even when the mailbox itself looks small. Free up space by deleting large attachments and emptying Trash and Spam (deleted items often still count against quota until purged), or ask your administrator to raise the allocation.

This one is easy to miss because outgoing mail keeps working normally — only inbound delivery breaks.

Are inbox rules or forwarding hiding your mail?

Filters and forwarding run automatically, so mail can be moved, archived, marked read, or deleted before you notice it arrived. Two layers are worth auditing:

1. Client-side rules. In Outlook, open Rules and look for anything that moves or deletes matching mail. In Gmail, open Settings → Filters and Blocked Addresses. A stale rule — "move anything from this domain to a folder" — is a frequent culprit, especially one a predecessor set up on a shared account.
2. Forwarding. If the account forwards to another address, a broken destination or a forwarding loop can drop mail. Check Settings → Forwarding and disable or repair anything pointing somewhere unexpected. Note that forwarding also breaks SPF alignment, which is why forwarded mail sometimes fails authentication at the final destination.

Also confirm the address isn't on a blocked-senders list — it is easy to block a domain by accident and then wonder why its mail vanished.

Are your domain's MX records correct?

If you run email on your own domain and no one can reach you, the problem is usually DNS. MX (Mail Exchanger) records tell the world which server accepts mail for your domain. If they are missing, pointing at a decommissioned host, or were overwritten during a migration, senders have nowhere to deliver and their messages bounce.

Verify the records from outside your own DNS panel, since the panel can show a value that hasn't propagated. Run your domain through Palisade's MX record lookup and confirm:

• The MX hostnames match your current provider (for example smtp.google.com for Google Workspace, or the mail.protection.outlook.com host for Microsoft 365).
• Each MX points at a hostname that itself resolves to an address — an MX pointing at a missing A record is a dead end.
• There are no leftover MX records from a previous provider competing with the current ones.

A broader DNS lookup shows every record at once, which helps when a migration left records half-changed. If you recently changed hosts, remember that DNS changes are not instant — allow up to 24–48 hours for propagation before assuming the records are wrong.

Is the sender being blocked or blocklisted?

When only one sender or one domain can't reach you, the block is specific rather than global. A few things can cause it:

• Your server is rejecting their IP. Business mail servers and security gateways maintain their own block rules. Check your provider's or gateway's admin console for a rejected-sender or connection log entry for that domain.
• A shared blocklist (DNSBL) lists the sender. Many mail servers reject connections from IPs on public blocklists. If a legitimate sender lands on one — often after a malware incident or a shared-IP neighbor's spam — their mail is refused until they delist.
• Their authentication is failing your policy. If the sender's SPF or DKIM fails and your inbound policy quarantines or rejects on failure, their mail never lands. Ask them to check their setup with an SPF checker.

If you suspect reputation, check the sending IP or domain against Palisade's domain reputation tool. And if the errors are Gmail- or Yahoo-specific, our guide to Yahoo and Gmail error codes decodes the exact responses their servers return.

Common issues with missing inbound email

Mail arrives late, sometimes an hour or more

This is usually greylisting. Many servers temporarily reject the first delivery attempt from an unknown sender and accept the retry a few minutes later — a cheap, effective spam filter. Legitimate servers always retry, so the mail arrives; it just looks "delayed." If a specific message is stuck rather than slow, our guide to email stuck in the queue covers the sender-side causes.

Some senders get through, others don't

Selective failure points at filtering or authentication, not infrastructure. If your MX records were broken, everyone would fail. Compare a working sender against a failing one: check whether the failing domain's mail is landing in spam, being caught by a rule, or failing your inbound authentication policy.

You stopped receiving mail after a domain or host migration

Migrations are the classic cause of a total inbound outage. The usual suspects are MX records still pointing at the old host, a lapsed DNS zone, or the new mailbox not yet provisioned. Re-run an MX lookup and confirm every record reflects the new provider, then send a test from an outside address.

A distribution list or shared mailbox receives nothing

Shared mailboxes and groups have their own membership and delivery settings. Confirm your address is still a member, that the group accepts external mail if the sender is outside your organization, and that no moderation rule is holding messages for approval.

Frequently asked questions

Why can I send emails but not receive them?

Sending and receiving use different paths. Outgoing mail leaves through your provider's SMTP service; incoming mail depends on your MX records, mailbox quota, and inbound filters. When sending works but receiving doesn't, the problem is almost always on the receiving side — a full mailbox, a filter or forwarding rule, or broken MX records — not your connection.

How do I test whether my email is being delivered at all?

Send a message from a completely separate account (a personal address on another provider) and watch what happens. If it bounces, read the bounce text — it names the reason, such as "mailbox full" or "no such user." If it silently disappears, the cause is filtering or forwarding on your side. Checking your domain's records with a DNS lookup rules out an infrastructure problem quickly.

Could my antivirus or security software be blocking email?

Yes. Desktop antivirus suites and email security gateways can quarantine messages before they reach your inbox, especially ones with attachments. Check the quarantine or held-messages area of whatever security product sits in front of your mailbox, and release any legitimate mail found there.

Does DMARC ever cause me to lose incoming mail?

DMARC governs how your domain's outbound mail is authenticated, but if your inbound gateway enforces senders' DMARC policies, a sender publishing p=reject whose mail fails authentication will be refused. That is the sender's misconfiguration to fix, not yours. You can confirm your own domain's policy with Palisade's DMARC checker.

Palisade automates the authentication side of this problem for MSPs and their clients: it monitors SPF, DKIM, and DMARC across every domain you manage, flags the misconfigurations that quietly send legitimate mail to spam, and turns raw DMARC reports into plain-language fixes. Run any domain through the free Email Security Score to see where it stands in about a minute.

Related reading

• Why is my email queued and how do I fix it?
• Why is Gmail rejecting my emails with a 550 error?
• How can you check and improve your email domain reputation?