UPDATE from Microsoft (even more, and more impacted services) - 3:06:31 p.m. PST Light at the end of the tunnel?
More info: Potentially impacted services include: - Exchange Online - Microsoft Teams - SharePoint Online - Microsoft Copilot 365 - Microsoft Defender XDR - Microsoft Planner - Microsoft To Do - Microsoft Intune - Microsoft Defender for Office 365 - Microsoft Purview: Multiple Purview services including Authorization, Auto Labelling, Data Loss Prevention (DLP), Communication Compliance, and Data Classification are impacted. - Power BI: All users may intermittently be unable to export reports with MIP sensitivity labels to PDF in Power BI. - Microsoft 365 Apps Admin Center: Multiple services including Cloud Update, Cloud Policy, and Inventory. - Universal Print: Users may encounter errors submitting print jobs or using admin features.
Current status: We've begun returning a portion of the affected servers to service, and they're remaining stable so far. We’ve also shifted traffic and connections to alternative pathways wherever possible and have observed limited recovery in some regions.
We've streamlined our recovery process to expedite returning the remaining affected servers to service. To further support recovery, we're implementing protective traffic management measures in a specific location to reduce load on the affected infrastructure, and we'll expand these measures to additional locations if we observe positive results. As capacity is restored, users may experience a gradual recovery as their clients reconnect to the service.
To validate a potential recovery approach, we're fully isolating a portion of our service infrastructure, restarting the affected components, and gradually reintroducing traffic to confirm our services remain stable before applying this approach more broadly. We're also analyzing traffic patterns across our entire service infrastructure and evaluating whether isolating traffic within each region may allow affected regions to recover independently.
Next update by: 4:30 p.m. PST
Posted Nov 12, 2026 - 15:13 PST
Update
UPDATE from Microsoft (even more impacted services) - at 2:11:39 p.m. PST
More info: Potentially impacted services include: - Exchange Online - Microsoft Teams - SharePoint Online - Microsoft Copilot 365 - Microsoft Defender XDR - Microsoft Planner - Microsoft To Do - Microsoft Intune - Microsoft Defender for Office 365 - Microsoft Purview: Multiple Purview services including Authorization, Auto Labelling, Data Loss Prevention (DLP), Communication Compliance, and Data Classification are impacted. - Power BI: All users may intermittently be unable to export reports with MIP sensitivity labels to PDF in Power BI. - Microsoft 365 Apps Admin Center: Multiple services including Cloud Update, Cloud Policy, and Inventory.
Current status: We’re continuing to pursue all available pathways to restore service, as our actions taken thus far have not provided the anticipated relief. Our investigation has found that a core process on the affected servers is becoming overwhelmed, which causes the servers to stop responding and contributes to the capacity loss.
To validate a potential recovery approach, we're fully isolating a portion of our service infrastructure, restarting the affected components, and gradually reintroducing traffic to confirm our services remain stable before applying this approach more broadly. We're also analyzing traffic patterns across our entire service infrastructure and evaluating whether isolating traffic within each region may allow affected regions to recover independently.
Previous status: We're continuing to work through restarting and validating the affected servers to safely return them to service, and we're exploring opportunities to expedite this process. In parallel, we're assessing whether reverting the small number of recent configuration updates we identified could help accelerate recovery.
Scope of impact: This issue may affect users attempting to access the affected Microsoft 365 services.
Next update by: 3:30 p.m. PST
Posted Nov 12, 2026 - 14:30 PST
Update
UPDATE (which is not much of an update - but added more impacted services) from Microsoft - at 12:44:51 p.m. PST
More info: Potentially impacted services include: - Exchange Online - Microsoft Teams (Pleasanton IT Note: MS Teams seems to be functional for our org) - SharePoint Online - Microsoft Copilot 365 - Microsoft Defender XDR - Microsoft Planner - Microsoft To Do
Current status: While validating the targeted change, we found that many of the affected servers have become unresponsive, which is preventing us from confirming whether the change is effective. We're restarting these servers so they can come back online with the change in place, and we're applying the same approach to additional affected portions of our infrastructure to validate the results more broadly.
Previous Status: While we haven't identified any recent changes that correlate with the start of impact, our investigation indicates the failed health checks may originate from a specific component on the affected servers that's responsible for processing them. We're deploying a targeted change to bypass this component on a subset of servers to validate whether this restores availability, and we've taken steps to prevent additional servers from being removed from service while we work to return the affected servers to service. We're also investigating why affected servers are experiencing elevated processor usage while handling requests.
Scope of impact: This issue may affect users attempting to access the affected Microsoft 365 services.
Next Update: 1:30 p.m. PST
Posted Nov 12, 2026 - 12:50 PST
Update
Microsoft 365 Outage: Additional Information and Community Discussion
In addition to our System Status Page, you can find more information in the IT Help Center: https://help.cityofpleasantonca.gov. Login is required.
Please continue to use the System Status Page for service updates and submit a service desk ticket if you need individual IT assistance.
Thank you for your patience and for helping one another.
Posted Nov 12, 2026 - 11:44 PST
Update
UPDATE from Microsoft - at 11:16:03 a.m. PST
Current status: We're aggressively pursuing all pathways to reduce impact. As a precaution, we've paused all deployments and configuration changes while we review recent changes for any correlation to this event. We've also moved traffic for some services off the affected infrastructure to further reduce load, with additional traffic moves in progress.
Scope of impact: This issue may affect users attempting to access the affected Microsoft 365 services.
Posted Nov 12, 2026 - 11:31 PST
Update
UPDATE from Microsoft - at 10:59:24 a.m. PST
User impact: Users may be unable to connect to multiple Microsoft 365 services.
More info: Potentially impacted services include: - Exchange Online - Microsoft Teams - SharePoint Online - Microsoft Copilot 365 - Microsoft Defender XDR
Current status: We've completed redistributing connection traffic across our worldwide infrastructure, and we're moving additional traffic off the affected infrastructure to further reduce load. We're also restarting affected servers to return them to service. In parallel, we're investigating whether the elevated traffic reflects a genuine increase in requests or a shift in how traffic is being routed across our infrastructure.
Scope of impact: This issue may affect users attempting to access the affected Microsoft 365 services.
Next Update from Microsoft: expected by 1:00 p.m. PST today
Posted Nov 12, 2026 - 11:12 PST
Update
From Microsoft: We're investigating reports of users experiencing issues accessing Exchange Online mailboxes through multiple connection methods in the Americas.
From Pleasanton IT: Impacts have been on our email services, Admin Console, and other hosted Microsoft services; MS Teams appears to be up, however.
Posted Nov 12, 2026 - 10:48 PST
Investigating
Many users are reporting trouble accessing Outlook on the web or delays receiving email. The issue appears widespread across our organization. We’re investigating whether it’s related to a Microsoft service disruption and will share updates as more information becomes available.
Posted Nov 12, 2026 - 10:27 PST
This incident affects: E-Mail Communications and Microsoft 365.