Updated November 12, 2026, 11:30 p.m. ET. This is a live situation. Microsoft has not given a time for full recovery, and we will update this page as things change.
The short answer
- This is a Microsoft problem, not yours. If Outlook, Teams or SharePoint will not load but other websites work, there is nothing wrong with your computer or your password.
- Do not reset passwords, rebuild Outlook profiles or reinstall Office. None of it helps, and it creates cleanup work once Microsoft recovers.
- Switch to the phone for anything urgent, and use files and mail already saved on your computer while the cloud is unavailable.
- Expect scams. Fake Microsoft and “IT support” calls, texts and emails always follow a big outage. Nobody legitimate will ask for your password or a sign-in code to fix this.
What happened
Shortly before 1 p.m. Eastern on Thursday, November 12, businesses across Canada, the United States and dozens of other countries lost access to Microsoft 365. Outlook stopped sending and receiving mail or would not open at all. Teams meetings failed, Copilot returned errors, and SharePoint and OneDrive files would not load. Microsoft tracked the incident in the admin center as MO1550821 and listed Exchange Online, Microsoft Teams, SharePoint Online, Microsoft 365 Copilot and Microsoft Defender XDR as affected, warning that users in any region could be hit.
The impact went well beyond missed emails. In Canada, a Toronto hospital network called a Code Grey, the alert used when critical infrastructure fails, and organizations including Via Rail, the Newfoundland and Labrador government and several health care providers lost email. Universities, school boards and city governments across North America fell back on phones and face-to-face conversations for the afternoon.
Microsoft says there is no sign of a cyberattack. Its updates through the evening explained that the extra load was not caused by more traffic, but by a number of servers unexpectedly dropping out of service and overwhelming the ones still running. The company reset affected servers, moved traffic onto other parts of its network and began rolling back a recent network change made around the time the problem started. Late Thursday it admitted those fixes were “not taking as expected”, because servers brought back online could stop responding again as soon as users reconnected.
This is also not the first long Microsoft 365 outage this year. North American customers lost Outlook and Teams for most of a day in January, and an Exchange Online problem in late August took hours to fix. For many offices, Thursday was a reminder of how much of the working day now runs through one provider.
Is it you or Microsoft? A two-minute check
| What you see | Likely cause today | What to do |
|---|---|---|
| Outlook says disconnected or messages sit in the Outbox | Microsoft outage | Leave them there. They should send when service returns. |
| Teams will not load, or meetings drop | Microsoft outage | Move the meeting to a phone call |
| SharePoint or OneDrive files will not open in the browser | Microsoft outage | Use copies already synced to your computer |
| Copilot errors or will not respond | Microsoft outage | Wait; nothing to fix locally |
| Nothing on the internet loads at all | Your connection, not Microsoft | Check the router, firewall or internet provider |
| Only one person has a problem while colleagues are fine | Probably local | Call your IT support as usual |
To confirm, check the Microsoft 365 Status page or the Microsoft 365 Status account on X. If your admins can reach the Microsoft 365 admin center, Service health shows the incident under MO1550821.
What to do right now
- Stop troubleshooting. Do not reset passwords, remove and re-add accounts, rebuild Outlook profiles or reinstall Office. Each of these makes recovery slower, and a reset password can lock people out of their phones and other apps.
- Work from what is already on your computer. Outlook on a desktop usually keeps a local copy of your recent mail, so you can still read and search it. OneDrive files marked to always stay on the device will open normally; files that live only in the cloud will not.
- Leave the Outbox alone. Messages waiting to send will usually go out once Microsoft recovers. Sending them again from another account can lead to duplicates and confusion.
- Pick up the phone for anything urgent. Call clients, suppliers and staff directly. Text meeting attendees a phone number instead of a Teams link.
- Tell people you are affected. A short line on your website, a changed phone greeting or a quick social post saves your team from repeating the same explanation all day.
- Keep client data in approved systems. Do not switch to personal Gmail or text messages to send contracts, health information or financial records. Privacy obligations do not pause during an outage.
- Keep a simple log. Note any deadlines missed, orders not confirmed or messages you know were due. It makes the catch-up much faster.
The scams that follow every outage
Criminals read the news too. Within hours of a major outage, fake “service restoration” emails, texts and phone calls start arriving, built to look like Microsoft or your own IT provider. Banks were already warning customers on Thursday that scammers may call offering to fix the Microsoft problem, and that they tend to switch to phone calls precisely because email is down.
| What arrives | What it asks for | What to do |
|---|---|---|
| A call from “Microsoft support” | Remote access to your computer, or payment to “restore” your account | Hang up. Microsoft does not call customers about outages. |
| An email or text saying you must sign in again to restore service | Your password and MFA code on a fake sign-in page | Do not click. Service returns on its own; you do not need to sign in through a link. |
| A call from someone claiming to be your IT team | Your MFA code or approval of a sign-in prompt | Hang up and call your IT provider on the number you already have |
| A supplier or client asking you to pay to new bank details “because email is down” | A payment to a different account | Confirm by phone on a number already in your files before paying anything |
| An offer of a refund or credit for the outage | Card or banking details | Ignore it. Any genuine credit appears in your Microsoft billing, not in a cold call. |
One rule for your whole team
No legitimate person will ever need your password, a sign-in code or remote control of your computer to fix a Microsoft outage. If anyone asks, end the conversation and call back on a number you already trust. This applies to calls that claim to be from us too.
Once service comes back
Recovery is rarely clean. Mail can arrive in bursts or out of order, some people will be back before others, and a few problems only show up the next morning. Work through this list as Microsoft restores service.
- Check Outboxes and Sent Items to confirm that queued messages actually went out.
- Look for bounce-back messages and resend anything that failed. Senders outside your company may have received delivery failures too, so tell key clients if you might have missed something.
- Check shared mailboxes and team inboxes, such as info@ or orders@, which are easy to overlook.
- Restart Outlook and Teams once, after Microsoft reports recovery, if they still show stale data.
- Review security alerts. Microsoft Defender XDR was among the affected services, so security alerts may have been delayed. Once it recovers, review anything raised during the outage window.
- Check sign-in activity. Look for unusual sign-ins, new inbox forwarding rules or MFA changes made while everyone was distracted.
- Take ten minutes for a lessons-learned chat. What stopped completely? What did people use instead? What would have made today easier?
Making the next outage less painful
No business can prevent a Microsoft outage, and moving away from Microsoft 365 rarely makes sense for a small or mid-sized company. What you can control is how much of your day stops when it happens.
| Weak point exposed on Thursday | Simple fix |
|---|---|
| Staff could not reach each other | A phone list or text group for the whole team, kept outside Microsoft 365 |
| Key documents only lived in the cloud | Critical files set to stay available offline on the people who need them |
| Clients did not know what was happening | A ready-made outage notice for your website and phone greeting |
| Nobody knew whether it was “just us” | Service health alerts sent to your IT provider and a named person inside the business |
| Scam calls arrived while people were confused | A standing call-back rule for anything involving passwords, codes or payments |
| Business-critical systems depended entirely on email | A second channel for orders, dispatch or patient communication |
Backups matter too, though not in the way people often expect. A Microsoft 365 backup will not keep email running during an outage, but it does protect you if data is lost or damaged in the confusion. Our guide to cloud vs local backup explains the options.
How IT Support Hub can help
For our managed clients, outages like this are part of the job. We watch Microsoft’s service health for every tenant we manage, so we can tell your staff it is a Microsoft problem before they start rebooting computers. We field the calls, track the incident through to recovery, then check mail flow, bounced messages, security alerts and sign-in activity afterwards. If someone receives a suspicious “support” call, they can ring us to check it before doing anything.
If you are not a client and need help today, call us at 647-812-3775. Emergencies are handled around the clock by phone. We can confirm whether a problem is local or Microsoft’s, help you get urgent work moving, and do the post-outage checks once service returns.
- Microsoft 365 support for tenant health, mail flow and post-outage cleanup
- Managed IT services with monitoring, help desk and on-site support across the GTA
- Cybersecurity services, including phishing protection and staff training
- Emergency IT support when something business-critical is down
For more on the scams that follow events like this, see our guides to email security for business and multi-factor authentication.