Outlook Not Receiving Emails? Find Where the Mail Is Stopping

When Outlook stops receiving email, the message is stuck in one of three places: your Outlook app isn’t showing it, your mailbox received it but filed it somewhere you didn’t look, or it never reached your mailbox. Each has a different fix, so find the place before changing anything.

The quickest test, and the first one Microsoft gives admins, is to sign in to Outlook on the web and look for the missing message. Use outlook.office.com for a work or school account, or outlook.com for a personal one. If your email comes from a web host or internet provider instead, use that provider’s webmail; for Gmail or Google Workspace, see Gmail not receiving emails.

If the message is there, your mailbox is fine and the problem is the Outlook app on your computer or phone. If it isn’t, the cause is rules, filtering or delivery, and reinstalling Outlook won’t help.

Read the result of the web test

Match what you saw to a row below and skip to that fix.

If you can’t send either, start with Outlook not sending emails. An account that can do neither usually has a connection or sign-in problem, or a full mailbox.

Mail is online but not in Outlook

Classic Outlook for Windows

Classic Outlook shows a local copy of your mailbox, so it can fall behind the server. That’s the usual cause of an Outlook inbox not updating while the web version is current. Check these in order:

• Work Offline. On the Send / Receive tab, make sure Work Offline isn’t highlighted. If the status bar says Disconnected, see Outlook disconnected from the server.
• A view filter. An Unread filter or a custom view can hide new mail. On the View tab, choose Reset View.
• Messages stuck before the Inbox. Microsoft documents a case where new mail syncs to the PC but never appears in the Inbox. Close Outlook and run outlook.exe /cleanips from Windows key + R. If that fails, right-click Inbox > Properties > General > Clear Offline Items, then press Shift+F9 with the Inbox selected.

If several folders are out of date, rebuild the local cache by renaming the .ost file, as covered in our guide to fixing Outlook when it won’t open. For an IMAP account, move the calendar and contacts out first, because they exist only in that file.

The new Outlook, Outlook for Mac and the Outlook mobile app

The new Outlook for Windows reads the same cloud mailbox as Outlook on the web, so a gap between them usually means a filter or Focused Inbox, not a sync failure. Close and reopen the app, then check the Other tab.

On a Mac with a Microsoft 365 mailbox, first turn off the Legacy Outlook switch if it’s on: from October 2026, the legacy app no longer works with Exchange Online. In Outlook for Mac or the Outlook mobile app, remove the account and add it again; Microsoft 365, Exchange, Outlook.com and IMAP mail stays on the server. Send or save anything in the Outbox first. Don’t do this with a POP account: POP usually deletes mail from the server after downloading it, so the device may hold the only copy.

If Apple’s Mail app falls behind, set the account to Push, or a short Fetch interval if Push isn’t offered, under Settings > Apps > Mail > Mail Accounts > Fetch New Data.

Email from a web host or internet provider (IMAP or POP)

Outlook on the web won’t show a mailbox from your website host or internet provider, so do the test above in the provider’s webmail. Then check:

• Mail only arrives when you click Send/Receive. Classic Outlook checks POP and IMAP accounts on a schedule. On the Send / Receive tab, open Send/Receive Groups > Define Send/Receive Groups, select All Accounts and tick Schedule an automatic send/receive every. Press F9 to check right away.
• Mail reaches one device but not another. A device set up with POP downloads each message and can delete it from the server before your other devices see it. On each POP device, turn on leaving a copy on the server, or switch to IMAP after saving any mail stored only on that device.

Rules, Junk, Focused Inbox and forwarding

If the message is in your mailbox but not where you expected, something moved it. Check these places in order:

1. Focused Inbox. Mail Outlook considers less important goes to the Other tab. In classic Outlook the setting is on the View tab; in the new Outlook and on the web it’s under Settings > Mail > Layout.
2. Junk Email and blocked senders. Outlook emails going to junk? Check the Junk Email folder, then the blocked list: Settings > Mail > Junk email in the new Outlook and on the web, or Home > Block (Junk in older versions) > Junk E-mail Options > Blocked Senders in classic Outlook.
3. Rules. Most rules run on the server, so a rule created months ago on another computer or phone still moves mail. Look under Settings > Mail > Rules, or File > Manage Rules & Alerts in classic Outlook. On Outlook.com, check Sweep too.
4. Forwarding. Under Settings > Mail > Forwarding, make sure mail isn’t being sent elsewhere without a copy kept.
5. Search everything. Search all folders, including Archive and Deleted Items. If search itself seems to miss mail, see Outlook search not working.

A warning: a rule or forwarding address you didn’t create, especially one that deletes or hides replies, is a common sign that someone else has access to the mailbox. Don’t just delete the rule; change the password, sign out all sessions and read signs your business has been compromised.

Mail isn’t reaching the mailbox

If the message isn’t anywhere in Outlook on the web, including Junk Email and Deleted Items, it most likely never arrived. One exception: a rule that permanently deletes or redirects mail can make a delivered message vanish, and message trace shows that as Delivered. The usual reasons mail never arrives:

• The mailbox is full. Classic Outlook shows a size bar under File > Info. Microsoft warns first, then blocks sending, then blocks receiving at the plan’s limit: 100 GB for most current Microsoft 365 business plans, 50 GB for Office 365 E1 and unlicensed shared mailboxes. Empty Deleted Items and ask your admin about an archive mailbox.
• Outlook.com storage is full. A free Outlook.com account has 15 GB of mail storage plus 5 GB of Microsoft cloud storage shared by OneDrive files and Outlook attachments. Going over either limit stops sending and receiving, even if the mailbox itself has room. Check both at Settings > Account > Storage.
• Your domain’s email records changed. If you recently changed email providers, moved your website or edited DNS, your MX record may now point somewhere else. A new MX record can take up to 72 hours to take effect everywhere.
• It was quarantined. Microsoft 365 can hold suspected spam and phishing instead of delivering it. You may get a quarantine notification; if not, your admin can check.
• Your license changed. A user whose Exchange Online license is removed loses access to the mailbox, and new mail stops with it.

Ask the sender to forward any bounce (non-delivery report). Its code usually names the cause:

For Microsoft 365 admins: trace the message

Message trace shows whether Microsoft 365 received the message and what it did with it.

Run a message trace

1. First rule out an outage: in the Microsoft 365 admin center, open Health > Service health and look at Exchange Online.
2. Run Microsoft’s automated check: in the admin center, select Help & support, type “email delivery” and open the email delivery troubleshooter. Enter the sender and recipient, then select Run Tests.
3. In the Exchange admin center (admin.exchange.microsoft.com), go to Mail flow > Message trace and click Start a trace. You need the Exchange Administrator role or Organization Management.
4. Enter the sender and recipient. The default range is two days; you can search back 90 days. A range of 10 days or less returns results almost immediately; a longer range comes back as a downloadable report that can take several hours.
5. Click a result to open its message events and details.

Reported status can lag five to ten minutes, and new trace data can take up to an hour to appear, so a missing result for a very recent message isn’t final.

Outside mail and shared addresses

For Outlook not receiving emails from external senders while internal mail arrives, start with the trace: no result means the message never reached Microsoft 365. Check the MX record status under Settings > Domains in the Microsoft 365 admin center, and the logs of any spam-filtering service in front of it.

Mail to a shared address such as info@ or sales@ often goes to a Microsoft 365 group or distribution list. Two settings cause most problems:

• Outside senders are rejected (bounce code 5.7.133). For a Microsoft 365 group, open Teams & groups > Active teams & groups in the admin center, select the group and, on the Settings tab, turn on Let people outside the organization email this group. For a distribution list, open Recipients > Groups in the Exchange admin center, select it, then Settings > Edit delivery management > Allow messages from people inside and outside my organization.
• Members don’t get a copy. A Microsoft 365 group created in the admin center keeps email in the group mailbox by default, not in members’ Inboxes. On the same Settings tab, turn on Send copies of group conversations and events to group members.

Check rules and sign-ins

• Mail flow rules: in the Exchange admin center, Mail flow > Rules. Look for rules that delete, redirect or quarantine messages.
• Users’ inbox rules: these don’t show in the admin center. In Exchange Online PowerShell, run Connect-ExchangeOnline, then Get-InboxRule -Mailbox user@yourdomain.com -IncludeHidden to list them, including hidden rules Outlook doesn’t display.
• Sign-in logs: if you find rules or forwarding nobody created, check Entra ID > Monitoring & health > Sign-in logs in the Microsoft Entra admin center for unfamiliar locations.

Our Microsoft 365 management covers the everyday admin side: adding and removing users, resetting passwords and setting up security such as MFA.

When to stop and get help

• Message trace says Delivered, the rules are clean and the user still can’t see the mail.
• You found rules or forwarding that nobody created. Treat it as a security incident, not a mail setting.
• Outside mail stopped right after a website, domain or DNS change, and you don’t have access to the DNS host.
• The mailbox is nearly full and needs an archive set up properly.

If you’d rather hand it off, tracking down why one user’s mail isn’t arriving is a typical $59 remote fix. For ongoing cover, the Business Support Plan includes Microsoft 365 administration and unlimited remote help desk tickets.

Common questions

Why am I getting emails from coworkers but not from outside senders?

Mail between coworkers in Microsoft 365 stays inside Microsoft’s service, so it keeps working even when your domain’s public email records are wrong. When only outside mail stops, check the MX record (Settings > Domains in the Microsoft 365 admin center), any spam-filtering service in front of Microsoft 365, and quarantine. A recent website or DNS change is a common trigger.

Why can I send emails but not receive them in Outlook?

Sending and receiving fail for different reasons, so a working Send button rules out less than you’d think. The usual causes are a rule or forwarding setting moving new mail, mail landing in Junk Email or the Other tab, or your domain’s MX record pointing somewhere else after a website or DNS change. Check Outlook on the web first: if the mail is there, the Outlook app on your computer is the problem.

Why do emails show on my phone but not in Outlook on my computer?

Your phone and Outlook on the web connect straight to the mailbox, while classic Outlook shows a local copy. When they disagree, the computer is the problem. Turn off Work Offline, reset the view, run outlook.exe /cleanips, or rebuild the .ost cache, after saving an IMAP account’s calendar and contacts, which live only in that file. The mail itself is safe on the server the whole time.

How long until a message shows up in message trace?

Microsoft notes a five to ten minute delay between a message’s actual and reported status, and its admin troubleshooting guide says trace data can take up to an hour to appear, so give it time before deciding a message never arrived. Any search covering 10 days or less returns results almost immediately, even for mail up to 90 days old. A range longer than 10 days comes back as a downloadable report that can take several hours to prepare.

Can a rule stop me from receiving emails without me knowing?

Yes. Most Outlook rules run on the server, so a rule created months ago on another device still moves or deletes new mail. Rules you don’t remember creating are also a warning sign that someone else has access to the account. Check Settings > Mail > Rules in Outlook on the web, and ask your admin to review sign-in logs if anything looks unfamiliar.

What happens when my Outlook mailbox is full?

Free Outlook.com accounts stop sending and receiving when either the 15 GB mailbox or the 5 GB of Microsoft cloud storage shared with OneDrive is full, and mail sent to an over-quota mailbox bounces. Microsoft 365 business mailboxes warn first, then block sending, then block receiving at 100 GB on most current plans. Delete large attachments, empty Deleted Items and Junk Email, or move old mail to an archive mailbox.

How can I tell if an email was quarantined?

An admin can run a message trace in the Exchange admin center; a status of Quarantined means Microsoft 365 held it. Admins review those messages in the Microsoft Defender portal under Email & collaboration > Review > Quarantine and should release one only after confirming with the sender that it’s legitimate. Depending on your organization’s policies, users may also get quarantine notifications and release some messages themselves.