My Outlook isn't sending or receiving emails. What should I check first?

The short answer: first, check whether Outlook is set to Work Offline and that your internet connection works. Then sign in to outlook.office.com in a web browser. If email works there, the problem is the Outlook app on your computer. If it doesn't, the problem is your mailbox or account, and that's a job for your IT person.

1. The quick checks

These sort out a surprising number of problems:

• Work Offline. In classic Outlook, look at the bottom of the window. If it says Working Offline or Disconnected, go to the Send / Receive tab and click Work Offline to turn it off.
• Internet connection. Can you open a website? If not, it's the connection, not Outlook.
• Send/Receive. In classic Outlook, click Send / Receive All Folders on the Send / Receive tab to give it a nudge.
• Restart. Close Outlook completely and open it again. If that doesn't help, restart the computer. Yes, really.

2. Check Outlook on the web

This is the most useful test there is, because it tells you where the problem lives.

1. Open a web browser and go to outlook.office.com.
2. Sign in with your work account.
3. See whether new emails are arriving, and try sending yourself a test message.

If it works on the web, your mailbox is fine and the problem is the Outlook app on your computer. Carry on with the steps below.

If it doesn't work on the web either, or you can't sign in, the problem is with your account or mailbox. Skip to "When to call IT". If you can't sign in at all, see I'm locked out of my Microsoft 365 account.

3. Check the Outbox

If emails aren't sending, look in your Outbox folder. An email stuck there is often the culprit, and it can hold up everything behind it.

• Large attachments are the usual cause. Business email has a size limit per message, and big files can also be very slow to send. Delete or move the stuck email to Drafts, then send the file as a OneDrive link instead of an attachment.
• If you can't open or delete the stuck email, switch on Work Offline, deal with the email, then switch it off again.

4. Check your mailbox isn't full

A full mailbox can stop you sending and, eventually, receiving. Outlook usually warns you first.

In classic Outlook, go to File and look for Mailbox Settings, which shows how much space is left. To make room, empty Deleted Items, clear out Sent Items, and delete old emails with big attachments. If you're always running out, your IT person can look at archiving or a bigger mailbox.

5. Check Junk and your rules

If you're expecting a particular email and it hasn't arrived:

• Look in Junk Email. If it's there, right-click it and mark it as Not junk.
• Check your rules. A rule you set up months ago might be moving those emails into another folder, or even deleting them. In classic Outlook, find Rules > Manage Rules & Alerts on the Home tab. In new Outlook and Outlook on the web, rules are under Settings > Mail > Rules.
• Use the search box to look in all folders.
• Ask the sender to check the email address they used, and whether they got a bounce message.

6. Update Office

Old versions of Outlook can develop odd problems. In classic Outlook, go to File > Office Account > Update Options > Update Now. Restart Outlook afterwards.

When to call IT

Call your IT person straight away if:

• several people in your business have the same problem at once. That points to something bigger than your laptop;
• Outlook on the web isn't working either;
• you get a bounce message saying your message was blocked or that you've been restricted from sending. This can mean Microsoft has blocked your account for sending spam, which often means someone has got into it and used it to send phishing emails. Treat it as urgent, and read how do I know if my email has been hacked?;
• people tell you they've had strange emails from you that you didn't send.

When you call, say what you've already tried and whether Outlook on the web works. It saves a lot of time.

Common questions

What's the difference between classic Outlook and new Outlook?

Microsoft is gradually moving people to new Outlook, which looks much like Outlook on the web. Some buttons in this guide, such as Work Offline, only exist in classic Outlook. If your Outlook has a toggle at the top saying New Outlook, you're on the new one.

Why can I get email on my phone but not on my laptop?

That's good news: your mailbox is working, and the problem is just the Outlook app on the laptop. Work through steps 1, 3 and 6. If it's still stuck, your IT person may need to repair or reset Outlook's profile.

Someone says my email bounced. What does that mean?

A bounce is an automatic reply saying an email couldn't be delivered. Ask them to forward it to you. The wording usually explains why, for example a full mailbox or a mistyped address, and it's very useful for your IT person.