--- title: "Microsoft Outlook Outage November 12: What to Check Now" description: "Outlook outage November 12: Microsoft's incident EX1550543 began 11:17 a.m. Eastern. Queued mail is retried, so check Message Trace before you resend." url: "https://webleveling.com/blog/microsoft-365-outlook-outage-november-2026/" lang: "en" published: "2026-11-13" modified: "2026-11-13" author: "Cal Hewitt" tags: ["email-marketing","small-business","website-maintenance"] image: "https://webleveling.com/og/blog-microsoft-365-outlook-outage-november-2026.jpg" alternates: es: "https://webleveling.com/es/blog/caida-de-outlook-noviembre-2026.md" --- # Microsoft Outlook Outage November 12: What to Check Now Outlook outage November 12: Microsoft's incident EX1550543 began 11:17 a.m. Eastern. Queued mail is retried, so check Message Trace before you resend. ![A catering company owner at the stainless prep counter of a bright commercial kitchen, flour on her apron, holding a phone angled away from the camera and frowning at it, unfilled sandwich platters beside her.](https://webleveling.com/blog/microsoft-365-outlook-outage-november-2026/outlook-outage-featured.jpg) Microsoft logged incident EX1550543 at 11:17 a.m. Eastern (16:17 UTC) on Thursday, November 12, when some people could not open their Exchange Online mailboxes. Exchange Online is the service behind business email in Microsoft 365. According to Microsoft's incident text as quoted by outage trackers, the trouble reached Outlook on the web, desktop Outlook, phone mail apps and the REST API. If your Outlook or Teams stopped that day, the fault was most likely Microsoft's, not your own setup. As of Microsoft's latest update on November 13, at 16:07 UTC (11:07 a.m. Eastern), the incident was still listed as [Service degradation](https://azureblog.co.uk/posts/microsoft-365-outage-12-november-2026/) and had not been declared resolved. Microsoft has not posted an end time yet, so check the current status in Service health in the Microsoft 365 admin center or on [Microsoft's public status page](https://status.cloud.microsoft/). Mail sent to you while your mailbox was out is usually held and retried rather than thrown away, and Microsoft extended the retry window to 48 hours for this incident. Microsoft has not said every message survived, though. Check Service health first, then Outbox and Sent Items for bounces, then Message Trace, Microsoft's record of what happened to each message, for anything important, and resend only what shows Failed or came back to you. **Key Takeaways** **Check Microsoft first** Incident EX1550543 began at 11:17 a.m. Eastern on November 12 and had not been declared resolved as of Microsoft's November 13 update at 16:07 UTC, so read the live status in Service health. **Look before you resend** Deferred mail is retried for one day under Microsoft's general rule and for 48 hours in this incident, so run Message Trace and resend only Failed, returned or unconfirmed mail. **Set up the next outage now** Turn on Service health email alerts, install the admin mobile app, and post a phone number or notice somewhere outside Microsoft 365. ## Find out in two minutes whether this was Microsoft or your setup The fastest way to settle it is to look at what Microsoft itself is showing for your account. Nothing in your office needs to be touched for that. An administrator with the Service Support or Helpdesk admin role can read Service health, and a short sequence tells you whether you are looking at a Microsoft problem or a local one. 1. **Sign in to the admin center**: Go to [admin.microsoft.com](https://admin.microsoft.com), choose Health, then Service health, and look for EX1550543 in the active issues or the issue history. 2. **Use the public page if you cannot sign in**: Microsoft points people who cannot reach the admin center to [status.cloud.microsoft](https://status.cloud.microsoft/) and to the @MSFT365Status account on X, as described in [Microsoft's service health guide](https://learn.microsoft.com/en-us/microsoft-365/enterprise/view-service-health). 3. **Report it if nothing is listed**: Service health has a Report an issue option for a problem Microsoft has not listed for your account. 4. **Compare notes**: If a coworker on a different network has the same trouble, that points away from your own router. On the cause, Microsoft's updates, as transcribed by Azure Blog UK, moved from "elevated load" to servers that had "become unexpectedly unavailable." Overnight into November 13, Microsoft began reverting a recent network configuration change that "correlates with the start of impact." Microsoft has not published a root cause and said a full Post-Incident Report would follow once the fix is complete. At 04:11 UTC on November 13 it said there was no indication of malicious activity. Two other Microsoft incidents are easy to mix up with this one. Teams incident TM1550488, covering delayed and failed chat messages, ran from 14:45 to 15:53 UTC on November 12 and was resolved. Exchange incident EX1545193, from November 6 to 9, was a separate problem in which legitimate mail to Outlook.com and Hotmail bounced; it has its own write-up in [Emails to Clients Bounced in November? What to Do Next](https://webleveling.com/blog/outlook-rejected-email-without-dmarc/). If you are unsure whether your own website or a provider is at fault in other situations, [how to tell if a website is down for everyone or just you](https://webleveling.com/blog/website-down-or-just-me/) walks through the same local-versus-provider test. EX1550543 as Microsoft described it (UTC, via Azure Blog UK) 1. 1 November 12, 16:17 Incident start time. Microsoft's first post, at 16:20, says it is investigating a potential issue with mailbox access. 2. 2 November 12, 18:19 Microsoft says infrastructure is under elevated load across multiple regions and begins restarts and traffic redirection. 3. 3 November 12, 19:43 Affected servers are failing automated health checks and are removed from service. 4. 4 November 13, 04:11 Microsoft says there is no indication this is the result of malicious activity. 5. 5 November 13, 09:10 Microsoft extends the email timeout window to 48 hours. 6. 6 November 13, 14:00 Email queues are described as significantly reduced and approaching normal levels. 7. 7 November 13, 16:07 Status still shows Service degradation; Microsoft has not declared the incident resolved. Microsoft first described the problem for the Americas and later said users in any region could be affected. Outlets reported Downdetector counts, but those are user reports, not a count of affected people, and Microsoft has not given a number. ![A catering van parked at the loading dock behind a strip of shops on an overcast noon, with its driver standing at the open back doors holding a clipboard and looking at a phone, deliveries unloaded beside him.](https://webleveling.com/blog/microsoft-365-outlook-outage-november-2026/outlook-outage-loading-dock.jpg) When mail stops at midday, orders and deliveries are the first things that go quiet. ## Know where your mail went while the mailbox was out Being unable to open a mailbox and losing messages are two different events. While Outlook would not connect, mail from outside could still be arriving at Microsoft's servers, and mail you sent could still be on its way. What happens next depends on whether the failure is temporary or permanent. Under [Microsoft's mail flow documentation](https://learn.microsoft.com/en-us/defender-office-365/mail-flow-about), deferred messages remain in Microsoft's queues for one day. The first few retries come 15 minutes or less apart, and the gaps widen to a maximum of 60 minutes. Permanent failures, the 500-series errors, return the message to the sender in a non-delivery report, often called a bounce. Queued messages are processed in the order they were received once service returns. How long deferred mail is retried | Situation | Retry window | Where it comes from | | --- | --- | --- | | General rule for Exchange Online | 1 day | Microsoft Learn, mail flow in Microsoft 365 | | This incident, from the November 13 update | 48 hours | Microsoft's 09:10 UTC update, as transcribed by Azure Blog UK | | Permanent (500-series) error | No retry; a bounce is returned | Microsoft Learn, mail flow in Microsoft 365 | Your own Service health page shows Microsoft's full incident text, including the 48-hour window, so check it there. The practical meaning is simple: a message that shows as Pending can still be delivered, and a message that bounced will not retry itself. Two cautions apply. A Sent Items entry shows that Outlook accepted the message, not that the recipient received it. And if you run a hybrid setup, with a mail server in your own office connected to Exchange Online, Microsoft warned that mail flow to and from that server may be affected, as WindowsForum paraphrased it, so check that path too. ## Read Message Trace and know which mail needs your attention Message Trace is Microsoft's own record of what happened to each message. It answers the question an inbox cannot: was this delivered, still being retried, or did it fail? An administrator runs it in the modern Exchange admin center or in PowerShell with Get-MessageTraceV2, and the steps are in [Microsoft's Message Trace guide for the new Exchange admin center](https://learn.microsoft.com/en-us/exchange/monitoring/trace-an-email-message/message-trace-modern-eac). Search by sender, recipient and a window from November 12 through November 13. Per [Microsoft's Message Trace FAQ](https://learn.microsoft.com/en-us/exchange/monitoring/trace-an-email-message/message-trace-faq), results appear right away for messages less than 10 days old, a newly sent message takes about 5 to 10 minutes to show up, and trace data is kept for 90 days. Run it for the handful of messages that matter, such as quotes, invoices and appointment confirmations, rather than the whole mailbox. What each Message Trace status means for you | Status | What it means | What to do | | --- | --- | --- | | Delivered | Microsoft handed the message to the recipient's mailbox | Nothing to resend | | Pending | A previous attempt failed and the service is trying again | Give it time; it can still deliver | | Failed | Delivery did not complete | Confirm the address, then resend | Microsoft's FAQ tells admins to look for a status of Failed or Pending when a message did not arrive. If nobody in your business has the admin access to run a trace, that is worth fixing before the next incident, and the last section covers it. ## Resend only what needs it and skip the duplicate flood Resending everything creates a second problem. Customers get two copies, some of which arrive after the first one finally delivers, and your own inbox fills with confused replies. A short rule keeps it clean. Resend a message when Message Trace shows Failed, when you received a bounce, or when you cannot confirm it arrived and the message cannot wait. For incoming mail, a customer who wrote to you on November 12 may be waiting on an answer you never saw. Ask the customers who matter most to resend anything they sent you that day, and say why. A quick phone call often settles a quote or a booking faster than a second email and avoids another round of waiting on a service that is still recovering. ![A woman in a work jacket standing on the sidewalk outside a church hall at dusk, phone held to her ear, writing a customer's name on a paper order pad balanced on her forearm, a catering van behind her.](https://webleveling.com/blog/microsoft-365-outlook-outage-november-2026/outlook-outage-call-client.jpg) Calling the customer who matters beats a second email into a mailbox that may still be recovering. Leave your own setup alone while Microsoft is working on its side. Reinstalling Outlook, resetting passwords or editing DNS records are changes on your end, and an incident listed in Service health is not something they repair. They can also leave you with sign-in or configuration work after the service returns. ## Set up alerts and a backup channel so the next outage costs less Most of the work that makes the next outage easy happens on a quiet day. [Microsoft's service health guide](https://learn.microsoft.com/en-us/microsoft-365/enterprise/view-service-health) covers three alerts an administrator can switch on. The fourth item below is a business step rather than a Microsoft recommendation. **Before the next outage** **Email alerts** In Service health, choose Customize, then Email, and add up to two addresses per admin account. Use an address outside Microsoft 365 for one of them. **Issue subscriptions** Open an incident and choose Manage notifications for this issue to get that incident's updates. **Mobile alerts** Install the Microsoft 365 Admin mobile app for push notifications, and follow @MSFT365Status on X. **A contact route outside Microsoft 365** Keep customer phone numbers, a voicemail greeting that says how to reach you, and a notice you can post on your website within minutes. When email is down, customers still need to reach you, so give them somewhere to go. A short line on your website that reads "Email is delayed today. Call or text us" does more for a customer than a silent inbox. The same message can go on your [Google Business Profile as a post](https://webleveling.com/blog/google-business-profile-posts/), which shows up where people find your phone number. Prepare the wording in advance so someone can publish it in a minute. ![A handwritten note taped to the glass door of a small catering shop at 8 a.m. in clear morning sun, the tape creased and the paper curling at one corner, reading "Email is down. Please call or text your order."](https://webleveling.com/blog/microsoft-365-outlook-outage-november-2026/outlook-outage-door-notice.jpg) A posted notice and a working phone number keep orders coming while email is out. ## Know when you can handle this yourself and when outside help pays off The checks above are a short administrator task with Microsoft's own tools. Reading Service health, running a few traces and resending what failed needs no redesign, no migration to another email provider and no emergency configuration change. Changing how your email is set up is not the answer to an incident that Microsoft is fixing on its side. Outside help earns its fee in four situations. You have no administrator access to Service health or Message Trace. Someone can run a trace but cannot read the result. Delivery problems keep coming back, outage or not. Or you need a written continuity plan that says who checks what, which numbers customers can call, and who updates the website notice. In any of those cases, a short written procedure and the right permissions in place beforehand are what turn a confusing afternoon into a ten-minute check. ![A catering shop counter at about 4 p.m. in warm afternoon light, the owner handing a paper bag and a receipt to a smiling customer, a handwritten pickup list on a clipboard beside the till.](https://webleveling.com/blog/microsoft-365-outlook-outage-november-2026/outlook-outage-pickup-counter.jpg) With the checks done and the notice up, the orders keep moving and customers keep coming in. **Quiz: Check what you know about the Outlook outage** 1. A message in your Sent Items shows what, as far as delivery goes? - Proof the recipient received it - That Outlook accepted the message, not that it was delivered **(correct answer)** - That Microsoft preserved a copy for 90 days - That it will arrive within the hour 2. In Message Trace, which status means you should confirm the address and resend? - Delivered - Pending - Failed **(correct answer)** - Queued for review 3. Which of these is a sensible first response to an incident listed in Service health? - Reinstall Outlook on every computer - Reset every password in the office - Read the incident status and check important mail in Message Trace **(correct answer)** - Edit your DNS records ## Frequently Asked Questions About the November 12 Outlook Outage **Was Outlook down on November 12?** Microsoft logged incident EX1550543 for Exchange Online mailbox access, with a start time of 11:17 a.m. Eastern (16:17 UTC) on November 12. Microsoft's updates said it could affect users in any region. **Is the Microsoft 365 outage fixed?** As of Microsoft's latest update on November 13, at 16:07 UTC, the incident was still listed as Service degradation and had not been declared resolved. Read the current status in Service health in the Microsoft 365 admin center or on the public status page. **Was my email lost?** Deferred mail is held and retried, one day under Microsoft's general rule and 48 hours for this incident per Microsoft's November 13 update. Microsoft has not said every message was preserved, so run Message Trace on the messages that matter. **Should I reinstall Outlook or reset passwords?** Leave them alone while an incident is open in Service health. Those changes are on your side and do not repair a problem on Microsoft's. **Was the outage a cyberattack?** At 04:11 UTC on November 13, Microsoft said there was no indication this was the result of malicious activity. Microsoft has not published a root cause, and a Post-Incident Report is promised after mitigation is complete. **Is this the same as the Teams outage or the November 6 to 9 incident?** No. Teams incident TM1550488 ran from 14:45 to 15:53 UTC on November 12 and was resolved. The November 6 to 9 incident, EX1545193, was about Outlook.com and Hotmail rejecting legitimate mail. ## Moving Forward The first move is to read Microsoft's status for EX1550543 in Service health, because the incident had not been declared resolved as of the November 13 update. After that, check your Outbox and Sent Items for bounces, run Message Trace on the mail that matters, and resend only what shows Failed, came back, or cannot be confirmed. Queued mail is retried for up to one day under Microsoft's general rule and 48 hours in this incident. Once the dust settles, the lasting gain is a short routine. Alerts that reach two people, an admin app on a phone, an address outside Microsoft 365 and a notice you can post in a minute turn the next outage into a calm check. If you want that routine set up and kept current, [Web Leveling](https://webleveling.com/) can help with the website side: keeping the outage notice and contact details accurate through our [website maintenance](https://webleveling.com/services/website-maintenance/) work, so customers always have a way to reach you. We work with small and medium businesses across the country and overseas. [Tell us how customers reach you when email is down](https://webleveling.com/contact/), and we will help you put the notice and the steps in writing. ## Terms Outage words in this post Tap a term to see what it means. **Exchange Online.** The Microsoft 365 service that hosts business mailboxes and delivers their email. **Service health.** The page in the Microsoft 365 admin center that lists Microsoft's active incidents and recent history. **Message Trace.** A Microsoft tool that shows whether a message was delivered, is still pending or failed. **Non-delivery report.** A bounce message returned to the sender when a message permanently fails to deliver. **Deferred message.** A message that could not be delivered yet and is being retried automatically. **Hybrid mail.** A setup where some mailboxes sit on a server in your own office and others in Exchange Online. 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What to Do Next](https://webleveling.com/blog/outlook-rejected-email-without-dmarc/): Microsoft says a spam rule update wrongly blocked mail to Outlook.com, Hotmail.com and Live.com in November 2026. Re-send what bounced, then check DMARC. - [Google November 2026 Core Update: Start Date and Expected Length](https://webleveling.com/blog/google-november-2026-core-update/): Rankings or calls moved this week? The Google November 2026 core update started November 10 and may take up to two weeks. Hold off on panic edits. - [New Website Not Showing on Google: Is the Wait Normal?](https://webleveling.com/blog/new-website-not-ranking-google-takes-time/): A new website not showing up on Google may simply need time. Google gave no fixed timeline, so check indexing, impressions and your Business Profile link.