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Status: Recovering / monitoring · Started Nov 12, 2026, 1:17 PM PST

Microsoft reference numbers: EX1550543, MO1550821, TM1550488, CR1550885, PP1550869

Microsoft says the Outlook, Teams and Microsoft 365 outage is being fixed and most services are recovering, though some users may still see intermittent problems. Delayed email is being held for up to 48 hours, so you do not need to take any action. We will confirm once Microsoft declares the service fully restored.

Affected: Exchange Online, Microsoft Teams, SharePoint Online, Microsoft 365 Copilot, Microsoft Defender XDR, Microsoft Defender for Office 365 (including Safe Links), Microsoft Planner, Microsoft To Do, Microsoft Intune, Microsoft Purview (some services)

Updates

• Nov 13, 2:36 PM PSTMicrosoft’s Friday statements report recovery progress and fewer Outlook reports, and an updated Microsoft 365 Status post reports early stabilization; no second MO1550821 advisory has appeared and no fix is declared.
• Nov 13, 2:23 PM PSTSecondary sources add a Friday timeline detail (returned servers failed again under traffic) and a report that Microsoft’s recent fixes fell short; no new Microsoft advisory for MO1550821 has appeared.
• Nov 13, 1:21 PM PSTNew items: Microsoft’s status posts now point admins to MO1550821 as well as EX1550543, a post names an overwhelmed core process as the capacity problem, and a mirror of Microsoft’s status shows the next update due around 5 PM on November 14.
• Nov 13, 12:20 PM PSTMicrosoft has publicly apologized and said there is no indication of a cyberattack, and a CNN-cited estimate puts the outage’s cost above $7 billion; no fix is declared and no second MO1550821 advisory has appeared.
• Nov 13, 11:19 AM PSTMicrosoft has attributed the incident to an earlier network capacity upgrade and says broad recovery is under way, but no fix is declared and no second MO1550821 advisory has appeared.
• Nov 13, 10:17 AM PSTNew since the last check: independent Kentik data shows Exchange Online traffic recovering and CNN reports Microsoft saying the underlying cause has been addressed; no fix is declared and no second MO1550821 advisory has appeared.
• Nov 13, 9:15 AM PSTNew since the last check: Microsoft’s own posts describe the failed server health checks and an alternative health-check method, the post-incident report timing has been reported, and Intune and Defender for Office 365 appear on the affected-services list. No fix is declared, and no second advisory for MO1550821 has appeared.
• Nov 13, 8:13 AM PSTOne new item: an independent Cloudflare-based timeline says the disruption started about 50 minutes before Microsoft opened MO1550821, while Microsoft still has not declared a fix.
• Nov 13, 7:12 AM PSTOne new item: a secondary report says Microsoft has started rolling out a patch to the Exchange fix, but no fix is declared and Microsoft has not confirmed it.
• Nov 13, 6:56 AM PSTMicrosoft has extended its email retry window to 48 hours, and Planner and To Do are listed as affected under MO1550821; no fix is declared and no second advisory has appeared.
• Nov 13, 6:40 AM PSTOne new detail: ABC7’s live blog reports Microsoft saying email queues are nearing normal levels; MO1550821 is still not declared fixed and no second advisory has appeared.
• Nov 13, 6:24 AM PSTOne new item: the Thursday Teams incident has an ID (TM1550488) and is reported resolved; nothing new on the main MO1550821 or EX1550543 fix status.
• Nov 13, 6:08 AM PSTMicrosoft says it is recovering frontend servers, is assessing whether reverting recent configuration updates could help, and is prioritising email queue and backlog reduction. No fix is declared.
• Nov 13, 5:52 AM PSTMinor new details: a new incident ID (PP1550869) to watch, Teams reported largely up, and the Microsoft 365 status page back online; no fix is declared.
• Nov 13, 5:36 AM PSTOne new detail: Microsoft’s latest MO1550821 update links traffic rebalancing to a surge in calls to backend servers and says it is adding virtual machines; nothing else new, and no fix is declared.
• Nov 13, 5:20 AM PSTNew: Australia’s government has activated its formal priority-restoration agreement with Microsoft; no fix is declared and the Microsoft advisories remain open.
• Nov 13, 5:04 AM PSTMicrosoft reports encouraging recovery progress in Europe, improving service in North America, and recovery in parts of Asia Pacific, but EX1550543 and MO1550821 are still not declared fixed.
• Nov 13, 4:48 AM PSTNew: servers that Microsoft brought back are failing again once traffic reaches them, and Microsoft says its fixes so far are not working as expected; no fix is declared.
• Nov 13, 4:32 AM PSTNew since the last check: a 5:28 a.m. Nov 13 Microsoft update reports some Outlook servers back in service and stable, and a secondary status page shows the incident still in degradation with recovery in phases. No fix is declared.
• Nov 13, 4:16 AM PSTNew since the last check: a later Microsoft 365 status post cites improvements in mailbox access and delayed email, OpenAI and Anthropic report failing Microsoft 365 connectors, and Microsoft’s Charles Lamanna has publicly apologised. MO1550821 is still not declared fixed.
• Nov 13, 4:00 AM PSTMicrosoft says its Dynamics 365 Contact Center agent access was restored at 00:57 GMT on Nov 13 under a separate incident, while the wider Microsoft 365 outage (MO1550821 / EX1550543) remains open.
• Nov 13, 3:44 AM PSTNew since the last check: Australian government agencies were among those hit, and Microsoft’s latest wording refers to a "current blocker" it is working through. No fix is declared.
• Nov 13, 3:28 AM PSTMicrosoft’s latest posts say it found no recent change tied to the start and that a server health-check component may be the cause; the outage is still not declared fixed.
• Nov 13, 3:12 AM PSTMicrosoft’s latest post says it is applying its traffic fixes more broadly, and a minister reports Microsoft’s view that the outage was not a cyberattack; no fix is declared.
• Nov 13, 2:40 AM PSTMicrosoft now reports "incremental improvement in several workloads" but says capacity has not fully returned to baseline. Still no fix declared for MO1550821 or EX1550543.
• Nov 13, 2:24 AM PSTMicrosoft’s 4:15 a.m. ET update reports early signs of stabilization, but capacity is not yet back to normal; MO1550821 and EX1550543 are still not declared fixed.
• Nov 13, 2:08 AM PSTNew since the last check: CNN reports Microsoft extended its email timeout window to 48 hours, NBC News lists Microsoft consumer services as affected, and an Australian cyber official is looking into the outage. Still no fix or all-clear.
• Nov 13, 1:52 AM PSTMinor new details: Microsoft revised its list of impacted services, and a WindowsForum report lists the Exchange connection methods affected. No fix or all-clear has been declared.
• Nov 13, 1:36 AM PSTNew since the last check: an Australian minister reports Microsoft’s view that a faulty software update caused the outage, and Microsoft’s own service-health wording on the partial patch is now quoted. No fix is declared.
• Nov 13, 1:20 AM PSTNew since the last check: The Register reports Microsoft has softened its wording on a cyberattack, a secondary report gives details of a partial patch, and Microsoft warned that inbound mail may be delayed. No fix is confirmed.
• Nov 13, 1:04 AM PSTTwo new items: a secondary report of a patch that is improving stability, and a Microsoft statement from Nov 12 saying mitigative actions restored some service health. Neither is a confirmed fix, and Microsoft’s latest posts still describe ongoing recovery.
• Nov 13, 12:48 AM PSTTwo small new details: Microsoft’s reported traffic-blocking measures and a secondary report that it began reverting a network configuration change. Still no confirmed fix for MO1550821 or EX1550543.
• Nov 13, 12:32 AM PSTLittle is new: Microsoft still has no confirmed fix, but a start-time discrepancy and a "partial recovery" wording turned up, and the MO1550821 status is unchanged at waiting.
• Nov 13, 12:16 AM PSTMicrosoft reports only "marginal success" so far, says it will publish a post-incident report once mitigated, and is adding traffic throttling and failover routing; there is still no confirmed fix or all-clear.
• Nov 13, 12:00 AM PSTNew since the last check: Microsoft says it is seeing "positive results" restarting servers, Downdetector reports spread to 74 countries, and NSW government services are affected. Still no confirmed fix or all-clear.
• Nov 12, 11:44 PM PSTMicrosoft still has no confirmed fix or all-clear for MO1550821 or EX1550543; the new items are a conflicting report on the cause, a Downdetector peak for wider Microsoft 365, and Exchange-dependency details.
• Nov 12, 11:28 PM PSTMicrosoft’s latest post says it is still recovering frontend servers and adding traffic optimization, and ABC reports a "gradual recovery" of access; no fix is confirmed.
• Nov 12, 11:12 PM PSTOne unconfirmed secondary report says Microsoft’s service health page now shows products as operational, which conflicts with Microsoft’s last statement that its fixes were not taking effect.
• Nov 12, 10:56 PM PSTSmall new items: a Downdetector count of about 20,000 by 11 p.m. ET Nov 12, a Microsoft 365 apps impact (recently used files), and an executive’s not-a-cyberattack statement; still no fix or restoration.
• Nov 12, 10:40 PM PSTSmall new items: Power BI is listed as affected, Microsoft is adding capacity including virtual machines, and phishing is exploiting the outage; still no fix or restoration.
• Nov 12, 10:23 PM PSTNew: Microsoft says it is rebuilding some affected servers on a previous software configuration to test whether they stay responsive, and that it is still working to pinpoint the cause; there is still no fix.
• Nov 12, 10:10 PM PSTNew since the last check: Downdetector counts fell to about 37,000 on Nov 12 (Tom’s Guide, unconfirmed), Windows Latest reports an SLA credit route, and Microsoft still has no fix or all-clear.
• Nov 12, 9:54 PM PSTNew: CNN reports Australia’s spy agency and federal police were hit, and Microsoft’s latest X post describes work on a "current blocker"; still no fix or restoration.
• Nov 12, 9:22 PM PSTMicrosoft’s own X posts say it is assessing whether reverting a few recent configuration updates could speed recovery, and that its actions so far have not given the expected relief; still no fix.
• Nov 12, 9:06 PM PSTOne minor new item: Microsoft said on the evening of Nov 12 that it is identifying alternate ways to add capacity. There is still no fix or restoration.
• Nov 12, 8:50 PM PSTNew since the last check: Microsoft said on Friday morning that its serviceability changes are not taking effect as expected, and ABC News’ live blog reports no long-term fix found yet. Still no fix or restoration.
• Nov 12, 8:33 PM PSTNew items: Australia’s Home Affairs Minister says Microsoft does not believe the outage was a cyber attack, and Microsoft’s impact list now includes Safe Links. There is still no fix or full restoration.
• Nov 12, 8:15 PM PSTOnly minor new items: an unconfirmed report that Microsoft began reversing a recent configuration change, and a separate exploited Outlook flaw (CVE-2026-124194) that Microsoft has not linked to the outage; still no fix or full restoration.
• Nov 12, 7:43 PM PSTNew items: OpenAI and Anthropic report problems with their Microsoft connectors, a copy of Microsoft’s status page shows ongoing capacity work, and an earlier Teams incident ID (TM1550488) has been reported. There is still no fix or full restoration.
• Nov 12, 7:26 PM PSTTwo minor new Microsoft details (load not caused by higher traffic; a secure-connection process overwhelmed on affected servers), with still no fix or full restoration.
• Nov 12, 7:20 PM PSTOne new detail: a university IT status page quoting Microsoft’s timeline says an alternative health check returned a subset of servers to service and an automated restart process is being prepared; no fix is confirmed.
• Nov 12, 7:04 PM PSTMinor new items only: an ABC News report that Australia’s cybersecurity chief is looking into the outage, Michigan’s state email problems, and a Microsoft statement of "positive results" from restarting servers. No fix or full restoration is confirmed.
• Nov 12, 6:48 PM PSTMicrosoft’s own status account says it has revised the list of impacted services under MO1550821, and a secondary report gives a next-update time; no fix or restoration is confirmed.
• Nov 12, 6:33 PM PSTOne new detail: Microsoft says it is testing a targeted change to bypass a component on some servers and is investigating high processor use. No fix or restoration is confirmed.
• Nov 12, 6:17 PM PSTMinor new items only: BusinessToday’s outage-scale figures and an unverified Ynetnews claim of restoration. Microsoft has still not confirmed a fix or full restoration, and MO1550821 remains open.
• Nov 12, 6:00 PM PSTMinor new detail: Microsoft says it is testing a configuration change for servers failing automated health checks; no fix is confirmed and MO1550821 is still open.
• Nov 12, 5:45 PM PSTMicrosoft says it is rebuilding some affected servers from a previous configuration to test whether they stay responsive, and Forbes Australia reports it has found overloaded software on the broken servers; no fix or full restoration is confirmed.
• Nov 12, 5:29 PM PSTMicrosoft says it is also limiting some traffic to the affected infrastructure as returned servers freeze again under use; there is still no fix or full restoration.
• Nov 12, 5:13 PM PSTMicrosoft says it has streamlined returning the remaining affected servers and warns that returned servers can become unresponsive again. There is still no fix or full restoration.
• Nov 12, 4:57 PM PSTOnly minor new items: Downdetector counts have fallen to about 40,000 per TechRadar, and an unconfirmed report says some users see Outlook back up; there is still no fix or full restoration from Microsoft.

Latest news

Microsoft says it has addressed the underlying issue and is still restoring service to remaining customers and regions, with recovery reported across North America, Europe and Asia Pacific. Some users may still see intermittent problems, and incidents EX1550543 and MO1550821 remain open.

We have addressed the underlying issue and continue to restore service to remaining customers and regions. Microsoft also apologized and said there is no indication the outage was malicious or cyber activity.

Microsoft, Nov 13, 2026, 9:34 AM PST · source

Is this a hack?

No — this is not a hack or cyberattack.

Microsoft says it has no evidence of malicious activity and has said the issue was not cyber or AI-agent related.

Root cause

Microsoft says the incident was introduced by an issue during an earlier network capacity upgrade that surfaced after a recent network change. Microsoft also says a core process on affected servers became overwhelmed, causing capacity loss; the exact trigger is not yet confirmed.

What the IT community is saying

Admins and users report Outlook, email and Teams still failing into the early hours of November 13 UTC, with several saying the outage has run for 12 hours or more. Q&A threads show people asking when service returns and noting that Microsoft’s latest update says Outlook is operational while their own access has not come back.

From public posts by IT administrators; not confirmed by the vendor.

Questions? Contact BIS Computer Solutions, Inc.

Phone: +1-818-248-5023 · Fax: +1-818-249-1169 · Email: support@biscomputer.com · Web: www.biscomputer.com

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