Your inbox has gone quiet, and it’s never at a convenient time. Before you assume the worst, work through these seven checks in order. In our experience, most “Outlook isn’t receiving email” problems are one of the first three.
Quick answer: If Outlook isn’t receiving email, check (1) you’re actually connected and not in Offline Mode, (2) your mailbox isn’t full, and (3) the emails aren’t being filtered into Junk or another folder. Then check your password and account status — a changed password or an expired Microsoft 365 license stops delivery silently.
1. Check Offline Mode and your connection
Outlook has an “Offline Mode” that’s easy to switch on by accident. Look at the bottom of the Outlook window: if it says “Working Offline” or “Disconnected,” that’s your problem. Go to the Send/Receive tab and click Work Offline to turn it off. While you’re at it, open a web page to confirm the office internet is actually up.
2. Check whether the mailbox is full
A full mailbox stops receiving — senders may get a bounce message, but you get silence. In Outlook on the web (outlook.office.com), check Settings → General → Storage. Microsoft 365 mailboxes are large, but shared mailboxes and older accounts fill up faster than people expect, especially with big attachments.
3. Look in Junk, Other, and your rules
Email “not arriving” is often email arriving somewhere else. Check Junk Email, the Other tab (if Focused Inbox is on), and any folders your rules might be filing into. Also search for the sender directly — if the message is in the account but not the Inbox, a rule or filter is moving it.
4. Confirm the password and account sign-in
If your Microsoft 365 password was changed recently — or your admin reset it — Outlook may be failing to sign in quietly. Open File → Account Settings and confirm the account shows no errors, or simply sign in at outlook.office.com. If the web version receives mail but desktop Outlook doesn’t, the desktop app is the problem, not your mailbox.
5. Send yourself a test from outside
Send a message from a personal account (Gmail, for example) to your work address. If it arrives in web Outlook, delivery is fine and the issue is your app or device. If it never arrives anywhere, the problem is on the delivery side — your domain’s mail settings (the MX records that tell the internet where your email lives) or your provider.
6. Check for a license or account hold
In Microsoft 365, an expired subscription or a removed license stops mail without much warning. If you’re the admin, check the account’s license status in the Microsoft 365 admin center. If you’re not the admin, this is the point to ask whoever manages your IT — this one can’t be fixed from Outlook.
7. Restart Outlook — properly
Close Outlook fully (check the system tray — it likes to keep running), reopen it, and watch the status bar. If it sits at “Trying to connect” for more than a few minutes after steps 1–6, the Outlook profile itself may be damaged, which means rebuilding the profile or the data file.
When it’s not a DIY fix
Call for help if: mail isn’t arriving in web Outlook either (delivery/DNS problem), the whole office is affected at once, you suspect a hacked account (mail missing and strange rules you didn’t create — that’s a red flag), or a license/account issue is locked behind an admin you don’t have. Those aren’t Outlook problems; they’re account and infrastructure problems, and poking at them can make recovery harder.
Want a hand with this? Book a free 15-minute diagnostic and we’ll pinpoint it on a call: Book your free 15-minute diagnostic — or, if email problems keep recurring, take the full free 30-minute IT assessment: Book your free 30-minute IT assessment Prefer reaching out another way? Book a free assessment through our contact page.
— Bill Thompson, On-Target Computers. Managed IT for small businesses and nonprofits in Fresno & Clovis. IT Done Right. (209) 741-4694