Microsoft Outlook/365 still down after 12 hours

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Microsoft 365 Status on X: "We’ve monitored the status of the changes applied to improve serviceability and confirmed they're not taking as expected. We’re identifying alternate workstreams that can be applied to increase capacity in the face of sustained traffic management imbalances. More info under EX1550543 and MO1550821 in the Microsoft 365 admin center, as well as https://t.co/7pjJdrpwOr if the admin center is not available to you."

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• Microsoft 365 Status@MSFT365Status13hWe're investigating reports of users experiencing issues accessing Exchange Online mailboxes through multiple connection methods in the Americas. More details can be found in the Microsoft 365 admin center under EX1550543.3.9K

• Microsoft 365 Status@MSFT365Status13hWhile we're working to mitigate impact, we've confirmed the issue may affect Microsoft 365 service connectivity for users in any region, more information will be provided in the Microsoft 365 admin center under EX1550543.498

• Microsoft 365 Status@MSFT365Status12hWe've determined a portion of infrastructure is experiencing elevated load across multiple regions, which is likely contributing to the connectivity errors. We're providing more information under EX1550543 and MO1550821 in the Microsoft 365 admin center, as well as status.cloud.microsoft186

• Microsoft 365 Status@MSFT365Status12hWe've begun redistributing connection traffic across our broader worldwide infrastructure to help balance the load. More info under EX1550543 and MO1550821 in the Microsoft 365 admin center, as well as status.cloud.microsoft if the admin center is not available to you.196

• Microsoft 365 Status@MSFT365Status12hWe're aggressively pursuing all pathways to reduce impact. We've paused all deployments, we're moving additional traffic off the affected infrastructure, and we're restarting affected servers to return them to service. More info under EX1550543 and MO1550821 in the Microsoft 365 admin center, as well as status.cloud.microsoft if the admin center is not available to you.364

• Microsoft 365 Status@MSFT365Status11hWe determined the elevated load isn't driven by an increase in traffic, but by a number of servers being unexpectedly unavailable; straining the remaining infrastructure. We're working to safely return them to service. More info under EX1550543 and MO1550821 in the Microsoft 365 admin center, as well as status.cloud.microsoft if the admin center is not available to you.238

• Microsoft 365 Status@MSFT365Status11hWe're testing a configuration change to address a problem that's causing servers to fail automated health checks and become unavailable. In parallel, we've initiated a restart of all affected servers and are monitoring health as they return to service. More info under EX1550543 and MO1550821 in the Microsoft 365 admin center, as well as status.cloud.microsoft if the admin center is not available to you.254

• Microsoft 365 Status@MSFT365Status11hWe've not identified any recent change correlated with the start of impact; however, our investigation indicates the failed health checks may originate from a specific component that's responsible for processing server health. We've taken steps to prevent additional servers from 292

• Microsoft 365 Status@MSFT365Status10hWe've validated an alternative service health check method, which allowed a subset of affected servers to successfully return to service. We're now applying this change more broadly. We're also preparing automated recovery systems to continually detect and restart unresponsive 245

• Microsoft 365 Status@MSFT365Status9hWe're actively restarting and validating the affected servers to return them to service. In parallel, we're assessing whether reverting a small number of recent configuration updates we identified could help accelerate recovery. More info under EX1550543 and MO1550821 in the Microsoft 365 admin center, as well as status.cloud.microsoft if the admin center is not available to you.274

• Microsoft 365 Status@MSFT365Status9hWe’re opening all available pathways to restore service, as our actions taken thus far have not provided the anticipated relief. We found a core process on affected servers is becoming overwhelmed, causing capacity loss. To validate a potential recovery, we're isolating a portion 994

• Microsoft 365 Status@MSFT365Status8hWe're returning a portion of affected servers to the service, and they remain stable so far. We're also shifting traffic to alternate routes wherever possible and observing limited recovery. In parallel, we've streamlined the process of returning the remaining affected servers to 370

• Microsoft 365 Status@MSFT365Status7hThe servers we returned to service can become unresponsive again once they receive traffic; we're analyzing diagnostic data to determine what's triggering the behavior. In parallel, we're temporarily limiting which types of traffic can reach the affected infrastructure in some 1K

• Microsoft 365 Status@MSFT365StatusWe’ve monitored the status of the changes applied to improve serviceability and confirmed they're not taking as expected. We’re identifying alternate workstreams that can be applied to increase capacity in the face of sustained traffic management imbalances. More info under EX1550543 and MO1550821 in the Microsoft 365 admin center, as well as msft.it/6013xBHsf if the admin center is not available to you.3:13 AM · Nov 13, 2026·4.1MViews1.4K

• BusinessBrush5179@Brush51793hThey spent 9 hours trying to hire back the 8000 employees that understood how the program worked.18

• Michael D. White@here4impact2h5

• MetaMom2012@metamom233h25