Microsoft reports continued improvement in the Microsoft 365 service disruption (tracked under MO1550821 and EX1550543).
Latest from Microsoft: Service availability continues to improve, and email queues have been significantly reduced and are approaching normal levels. Microsoft has put additional mitigation measures in place, is restoring the remaining affected infrastructure, and is investigating some lingering issues while closely monitoring service health and confirming recovery across all connection methods.
What you may notice: Most users should see email and Microsoft 365 services working again. Some users may still experience intermittent access issues or delayed email as recovery finishes. As queued messages are delivered, you may receive emails that were sent earlier during the outage, so some messages may arrive late or out of order.
Outlook prompt you may see: If Outlook asks to allow autodiscover.outlook.com to configure server settings, this is a legitimate Microsoft address and is safe to allow. If the prompt shows any other address, click Cancel and contact our support team.
What you should do: No action is needed on your end. If an important email you were expecting hasn't arrived, give it some time, as delayed messages are still being delivered. Please continue to be cautious of emails or calls claiming to be from Microsoft or IT support offering to fix the outage. The Netgain team continues to monitor and will share a final update once Microsoft confirms full resolution. If you continue to have issues after that point, please contact our support team.
Posted Nov 13, 2026 - 08:46 CST
Update
Microsoft continues to work on the service disruption affecting Outlook, Exchange Online, and other Microsoft 365 services (tracked under EX1550543 and MO1550821).
What happened: Microsoft has determined that a number of servers became unexpectedly unavailable after failing automated health checks. This put extra load on the remaining infrastructure, causing the connectivity issues users are seeing. The issue was first reported in the Americas, but Microsoft has confirmed it may affect users in any region.
What Microsoft is doing: Microsoft has paused all deployments, is moving traffic off the affected infrastructure, is testing a configuration change to address the underlying problem, and has started restarting all affected servers to bring them back into service.
What may be affected: Outlook desktop, Outlook on the web, and email on mobile devices Calendars and shared mailboxes Applications that connect to your mailbox, such as scan-to-email and practice management integrations Outlook within your virtual desktop Intermittent issues with Teams, OneDrive, or SharePoint What you should do: No action is needed on your end. Restarting your computer or reinstalling Outlook will not resolve this issue. Email sent to you during the disruption is generally queued and delivered once service recovers.
The Netgain team is monitoring closely and will share another update as service is restored. If issues continue after Microsoft reports the incident resolved, please contact our support team.
Posted Nov 12, 2026 - 14:00 CST
Update
We are continuing to monitor the issue
Posted Nov 12, 2026 - 13:29 CST
Identified
We are aware that Microsoft is currently experiencing a service disruption affecting Outlook and Exchange Online. Microsoft has confirmed it is investigating the issue, which centers on users having trouble accessing Exchange Online mailboxes through multiple connection methods in the Americas, and is working to rebalance and mitigate impact across the affected infrastructure. The incident is tracked under ID EX1550543 in the Microsoft 365 admin center.
What may be affected The connection methods potentially impacted include Outlook on the web, messaging API, Exchange ActiveSync, and REST. In practical terms, this means you may see problems with: Outlook desktop and Outlook on the web (sending, receiving, or opening your mailbox) Email on mobile phones and tablets Calendars and shared mailboxes Applications that connect to your mailbox, such as scan-to-email, CRM or practice management integrations, and other tools that send or read mail through Microsoft 365 Outlook within your virtual desktop, since it connects to the same Microsoft service Microsoft has also noted that the issue may affect Microsoft 365 service connectivity for users in any region, so you may notice intermittent issues with Teams, OneDrive, or SharePoint as well.
What you should do There is no action needed on your end, and restarting your computer or reinstalling Outlook will not resolve this issue. Messages sent to you during the disruption are generally queued and delivered once service recovers. If something urgent can’t wait, please use phone or Teams chat where available. The Netgain team is monitoring the incident and will share updates as Microsoft provides them. If you experience issues that continue after Microsoft reports the incident resolved, please contact our support team.