Microsoft Outlook Failure: Service Improves but Problems Persist

If you couldn’t open your email on Thursday or Friday, it wasn’t your fault. The Outlook failure and other Microsoft 365 services started failing just before 1 p.m. ET on Thursday, November 12, and continued into Friday, November 13. Although there was a partial recovery that morning, it’s still not back to normal.

What happened exactly?

According to CNBC, the outage affected Outlook, Teams, SharePoint, and Copilot, in addition to external services that connect with Microsoft products, such as Outlook Calendar.

In an update shortly after 7 a.m. ET on Friday, Microsoft spoke of «encouraging progress» in Europe. The company said the service is being restored gradually in the Asia-Pacific region and that the situation in North America is improving. However, it warned that intermittent problems will continue.

Do we know why it happened?

Not entirely. Microsoft initially attributed the problem to a heavy load on part of its infrastructure, with servers becoming unavailable and overloading the rest. Some servers were failing automatic status checks.

iTnews reports that the company has not yet revealed the final cause and will publish a complete report once it has fully corrected the problem. Microsoft also says that, for now, it has no evidence of malicious activity. Note: this is what the company claims at this time, not a definitive conclusion.

Australian Minister Tony Burke said, according to Reuters as cited by CNBC, that Microsoft believes it’s similar to the CrowdStrike case, an update that went wrong. This is his version of what the company explained to him, not a confirmed diagnosis.

What about the emails that didn’t arrive?

Microsoft extended to 48 hours the time during which delayed messages will continue to try to be delivered. This aims to protect them, but does not guarantee that all will be recovered. iTnews noted that some scheduled emails appeared with hours of disorder.

Who is affected and how?

Workers and families. The good news: Outlook has reopened for some, and the message queue is being processed. The bad news: intermittent issues may continue. In the UK, the National Health Service (NHS) said some services were affected, but patients should attend their appointments as usual. A hospital group warned of long wait times when calling.

Companies. According to CNBC, Richemont delayed its results slightly on Friday, and Workhorse Group rescheduled its results from November 12 to November 16. Air India temporarily redirected its emails to continue receiving customer messages and said its flights were not affected.

Governments. Burke explained that Australia activated a digital resilience agreement with Microsoft to prioritize its interests. iTnews points out that this may have influenced the fact that the Asia-Pacific region was among the first to recover.

Microsoft. The company says it is treating the case with urgency until it is fully mitigated. The report with the underlying cause is still pending.

What can you do in the meantime?

• If something is urgent, confirm it by phone instead of waiting for a response by email.
• Avoid re-sending messages en masse: you may duplicate the load and generate confusion if the originals arrive late.
• Be patient with late or disordered emails.
• You can check the status of the services at status.cloud.microsoft.

And you, how dependent are you on a single service?

Think about what would have happened if this had caught you on a day of deliveries, appointments, or procedures. Do you have another way to contact your boss, your clinic, or your clients? This note reflects the information available on Friday, November 13, and the situation may change.

If you want more context about the company, we have two previous notes about Microsoft: Microsoft promotes 6,000 jobs and H-1B visas and Microsoft. They are from other dates and deal with other topics, not this failure.

Sources: CNBC, Nov 13; iTnews, Nov 13. Data consulted on November 13, 2026.