On a day when so much of working life runs through a single inbox, Microsoft has found itself confronting a reminder of how fragile the invisible machinery of connection can be. For more than seven hours, Outlook and a wide range of Microsoft 365 services faltered across the globe, traced to a secure-connection process on affected servers that became overwhelmed and stopped answering requests. The company is now patiently widening its repairs, testing a configuration change on a small set of machines before asking the rest to follow, while also undoing a recent network change that happened to
Microsoft Expands Fixes for Seven-Hour Outlook Outage Linked to Overloaded Secure Connections
A process responsible for secure connections was becoming overwhelmed
Mark
Seven hours is a long time for email to be down. What actually broke?
Mimi
According to Microsoft, a process that sets up secure connections on certain servers got overwhelmed and the servers stopped processing requests.
Mark
So it wasn't one product failing, it was something underneath many of them.
Mimi
Right, that's why the list is so wide. Anything that leans on Exchange Online was hit: Outlook, Copilot, Planner, Power BI, Defender and more.
Luke
Careful with the word cause, though. Microsoft says a recent network configuration change coincided with the start of the outage and it's reverting it. That's timing, not a stated cause.
Mark
What's still working?
Mimi
Core Teams messaging and meetings, and files stored directly in SharePoint Online. Teams calendars and scheduling are affected because they depend on Exchange.
Luke
And that's Microsoft's description. The update says largely functional, so some people may still see problems there.
Mark
How is the fix going?
Mimi
Carefully. Traffic limits are in place in specific locations, and Microsoft will add traffic back only once the servers prove stable. A configuration change is being tested on a subset of servers first.
Luke
Worth noting what we don't have: how many users or organisations were affected, and when full recovery is expected. The update gives neither.
El Pulso
- Outlook on the web and desktop, Exchange ActiveSync and email delivery went dark for users worldwide, with delayed messages piling up behind them.
- Copilot Chat, Teams calendars, Planner, Power BI and admin centre pages stalled as the disruption spread across dependent services.
- Microsoft is restoring traffic in cautious stages, watching servers closely after temporary restrictions were placed on specific locations.
- A configuration fix is being validated on a subset of servers before broad rollout, with infrastructure restarts still ahead.
- A recent network change is being reversed, though the company has not confirmed it caused the failure, only that the timing aligned.
- Teams messaging, online meetings and SharePoint files remain largely working, so recovery is landing unevenly but steadily.
On a day when so much of working life runs through a single inbox, Microsoft has found itself confronting a reminder of how fragile the invisible machinery of connection can be. For more than seven hours, Outlook and a wide range of Microsoft 365 services faltered across the globe, traced to a secure-connection process on affected servers that became overwhelmed and stopped answering requests. The company is now patiently widening its repairs, testing a configuration change on a small set of machines before asking the rest to follow, while also undoing a recent network change that happened to coincide with the trouble. The recovery is measured rather than sudden, and what will matter most is whether the servers hold steady as traffic returns.
Microsoft says it is widening its corrective measures after a global outage knocked out Outlook and a range of Microsoft 365 services for more than seven hours. In its latest update, the company reported it was watching affected servers closely after placing temporary traffic restrictions at specific locations.
The path back is deliberately gradual. Additional traffic will only return once the servers prove stable handling a narrower set of connections, and the repairs will expand as that stability holds. The investigation pinpointed a process that establishes secure connections on those servers, which became overwhelmed and caused them to stop processing requests.
A configuration change is being prepared to fix the problem across all affected servers. It is being validated on a subset first, and the work will involve restarting parts of the infrastructure. At the same time, Microsoft has begun reverting a recent network configuration change that coincided with the disruption, though it has not claimed that change caused the failure.
For users, the impact reached deep into email and work tools. Mailboxes were out of reach through Outlook web, desktop and mobile connections, email delivery slowed, and some admin pages and recently used files would not appear. Copilot Chat struggled to load or reach work data, and a long list of other products was affected. Teams held up better: messaging, meetings and SharePoint files largely work, while calendars and scheduling depend on Exchange and may fail. Microsoft will keep watching whether the fix holds on the test servers and whether traffic can be restored in stages without another faltering.
Microsoft said it is widening its corrective measures after a global outage knocked out Outlook and a range of Microsoft 365 services for more than seven hours. In its most recent update, the company said it was watching the affected servers after putting temporary traffic restrictions in place at specific locations.
The plan from here is gradual. Microsoft said it would bring additional traffic back only after confirming that the servers stayed stable while handling a narrower set of connections. It added that the corrective measures would be expanded as stability was established with the changes already applied.
The company's investigation pointed to a specific failure. A process responsible for establishing secure connections on the affected servers was becoming overwhelmed, and that caused the servers to stop processing requests.
Microsoft is preparing a configuration change to address the problem across all affected servers. It is first validating the change on a subset of servers before applying it more widely, and the work includes restarts of the affected infrastructure.
In parallel, the company has begun reverting a recent network configuration change that coincided with the start of the disruption. Microsoft said it is monitoring whether undoing that change contributes to recovery. The update does not say the network change caused the failure, only that the timing lined up.
The outage has hit services and features that interact with Exchange Online and email. Users may be unable to reach their mailboxes through Outlook on the web, Outlook desktop, Exchange ActiveSync or REST-based connections, and email delivery may be delayed. Some Microsoft 365 admin centre pages may not load, and people may be unable to see their recently used files in Microsoft 365 apps.
Copilot Chat users may find that the service will not load or does not respond in the web and desktop apps. Copilot may also be unable to reach work data, including emails, calendars and files. The list of other affected products is long: Microsoft Planner, Microsoft To Do, Microsoft Purview, Microsoft Defender, Microsoft Graph, Power BI, Universal Print and certain Windows 365 functions.
Teams is partly affected. Features that depend on Exchange Online, such as calendars and meeting scheduling, may fail. Core messaging and online meetings remain largely functional, though, and so does access to files stored directly in SharePoint Online. Microsoft said elements of these services that do not depend on Exchange Online continue to work.
Microsoft said it would keep monitoring the affected servers and assessing the effect of its corrective measures. The next markers are whether the configuration change holds up on the test subset of servers, and whether traffic can be restored in stages without the servers faltering again.
Citas Notables
Microsoft will reintroduce additional traffic gradually once servers are confirmed stable, and expand corrective measures as stability is established.— Microsoft, in its latest service update
Quieres la nota completa?
Lee el original en India Today ↗