Outlook not working: how the Microsoft outage affects your email
Outlook keeps loading, repeatedly asks for your password or shows an empty inbox. Since Thursday 12 November 2026, for many organisations that isn't down to their own computer but to an outage in Exchange Online, the email service of Microsoft 365. Here you can read what's going on, what you'd better not do and how to keep your email safe.
If Outlook isn't working with a business Microsoft 365 account, the Exchange Online outage is very likely the cause. Reinstalling or deleting your profile won't help and can make recovery harder.
Below you can see which forms of Outlook were affected, what happens to incoming email and what you can do. Status as of Friday 13 November 2026, 10:15.
Why Outlook isn't working right now
- The outage is in Exchange Online, the service that stores business mailboxes in Microsoft 365.
- Outlook on the web, Outlook for Windows and Mac, and the mail app on your phone can all be affected.
- Email may arrive with a delay. Microsoft reports delays, not lost messages.
- Reinstalling, deleting profiles or repeatedly signing in again won't fix it.
- For anything that can't wait, use the phone or another channel.
Outlook is the program, Exchange Online is the service behind it. Your mailbox, calendar and contacts are stored by Microsoft in Exchange Online, and Outlook retrieves them from there. On Thursday 12 November at around 17:15 Dutch time, users in North and South America began reporting problems opening their mailbox (NOS). Later that evening, Microsoft wrote that users in any region could be affected (BleepingComputer).
According to Microsoft, the overload is not caused by increased traffic, but by a number of servers unexpectedly dropping out and the remaining servers being unable to cope with the workload (@MSFT365Status on X). A process that sets up secure connections became overloaded as a result (ABC7). For you as a user, that means Outlook may start up, but cannot connect to your mailbox.
Which versions of Outlook are affected
On Microsoft's status page, Microsoft lists four ways in which users may be unable to reach their mailbox. These are exactly the ways in which almost everyone reads email.
What Microsoft reports about Exchange Online, status as of 13 November 2026, 10:15
| How you read email | What you notice | What Microsoft reports |
|---|---|---|
| Outlook on the web (outlook.office.com) | Won't load, keeps spinning or shows an error message | Mailbox may be unreachable |
| Outlook for Windows or Mac | Status shows Disconnected or Updating | Mailbox may be unreachable via MAPI |
| Email on your phone (Outlook app or built-in mail) | No new messages, sending fails | Mobile synchronisation via ActiveSync and REST affected |
| Incoming email | Messages arrive later than normal | Delivery may be delayed |
Calendars also depend on Exchange Online. That is why meeting requests and the calendar in Teams are now working poorly too, while calling and chatting in Teams largely continue. You can read more in the article on Teams during the outage.
If you use a personal address with Outlook.com or Hotmail, that may be affected too: according to ITdaily, Microsoft also reported problems on the consumer status page. Business and personal accounts do run on different environments, though, so your experience may differ.
What not to do
When there's an outage, the reflex is to try to fix something yourself. With this outage, that often makes things worse. An Outlook profile that you delete has to synchronise completely from scratch after recovery, and with a large mailbox that takes a lot of time. If you remove your account on a phone and add it again, you won't be able to sign in again during the outage.
- Don't reinstall
Outlook itself isn't broken. Reinstalling fixes nothing and wastes time.
- Leave your profile or account in place
Don't delete an Outlook profile or an account on your phone. Once service is restored, everything will synchronise automatically.
- Don't keep signing in again
Repeated failed sign-in attempts can trigger additional security checks. It is better to wait a while.
- Don't act on recovery emails
Messages asking you to sign in again or recover your mailbox are often phishing during an outage.
What you can do
First check whether it really is the outage. On status.cloud.microsoft you can see the public status, and your administrator can see incidents EX1550543 and MO1550821 in the Microsoft 365 admin centre. How to do that, and how to rule out that the problem lies in your own environment, is explained in the article on checking the status.
If you already have Outlook for Windows or Mac open, leave it open. Email that was synchronised earlier is stored locally on your computer and can still be read and searched. Anything you send now stays in the Outbox and goes out automatically once the connection is back. Don't leave important email there that has to arrive on time without also arranging it another way.
If something has to go to a customer or supplier today, call them or use a channel that doesn't run on Microsoft 365. Briefly record what you agreed that way, so it ends up in the file later.
Microsoft reports delayed delivery, not lost messages, and on Friday morning extended the window within which delayed email is still delivered to 48 hours. If you are waiting for an important email, ask the sender whether it has been sent, and once service is restored also check your Junk Email folder and quarantine.
When Outlook works again
After recovery it can take a while for everything to catch up. Outlook has to retrieve what arrived in the meantime, and email from Microsoft's queue may arrive all at once. Check that messages in your Outbox have been sent and that an important email has actually arrived, for example by asking the recipient.
Once service is restored, administrators review quarantine and message queues. According to Microsoft, items in Defender for Office 365 could not always be released from quarantine during the outage. What that means for security and administration is covered in the article on Intune, Defender and Copilot.
For the timeline and all affected services, read the overview of the Microsoft 365 outage.
ways to read email that Microsoft lists as affected: web, desktop, mobile sync and REST.
reports about Outlook at the peak on Downdetector, according to ITdaily.
the incident number for Exchange Online in the Microsoft 365 admin centre.
Frequently asked questions
About Outlook during the Microsoft 365 outage of November 2026.
Why isn't Outlook working?
Since 12 November 2026, Exchange Online has been disrupted. This is the service that hosts Microsoft 365 business mailboxes. Outlook is then unable to connect to your mailbox.
Will I lose email because of the outage?
Microsoft reports that delivery may be delayed, not that messages are being lost. After recovery, do check that important email has arrived.
Do I need to reinstall Outlook?
No. Outlook itself isn't broken. Reinstalling it or deleting your profile won't help and will cost extra time after recovery.
Is Outlook on my phone not working either?
It may not be. Microsoft also lists mobile synchronisation as affected. Don't remove the account from your phone, as you may not be able to add it again during the outage.
Are Outlook.com and Hotmail down too?
Problems have also been reported with consumer services. Business and personal accounts run on different environments, so your experience may differ.
How do I know when Outlook is working again?
Follow status.cloud.microsoft or ask your administrator about incident EX1550543 in the admin centre. Microsoft has not yet given a time for full recovery.
Does your software depend on Outlook or Exchange?
Appfront builds custom software and integrations with Microsoft 365. Want your own systems to keep working when Microsoft's email falters? Schedule a conversation with a developer.