Microsoft 365 and Outlook suffer global outage on Thursday, 12 November

What users experienced

Microsoft 365 and its Outlook email service stopped working on Thursday evening, 12 November, according to Fanpage, which placed the start at about 18:40 Italian time. Users reported failed logins, connection problems and apps that did not work, and the disruption was not limited to one country. Adnkronos listed reports from Italy, the United States, France and Canada, where people could neither send nor receive email. Fanpage counted more than 1,000 Downdetector reports for the email service and about 400 for the Microsoft Office subscription suite at the time it wrote. Fanpage said the causes were not known.

Reports in Switzerland and the Americas

According to 20 Minuten, Microsoft 365 posted on X at about 19:00 that it was investigating reports of users in North and South America who could not reach Exchange Online mailboxes through various connection methods. The outlet said the business version of the applications appeared to be the one affected. Swiss users reported problems too: more than 50 people logged issues with Microsoft 365 on allestörungen.ch on Thursday evening, and nearly 100 reported problems with Outlook. Blick said the Teams meeting tool was also affected, alongside Outlook Exchange mailboxes.

Microsoft's response

Microsoft said through its social media channels that it was working to mitigate the impact and that the problem could affect connectivity to Microsoft 365 services for users in any geographic area. A further message from the company's account at 19:20 said the same, according to 20 Minuten. Blick reported that Microsoft pointed users to the admin center on its website for further information.

Possible cause

The company's update said part of its infrastructure in several regions was experiencing increased load, which probably contributed to the connection failures. 20 Minuten said this could point to a DDoS attack, a cyberattack that overwhelms a system with a flood of requests in a very short time, but that no attack had been confirmed.

Status at the latest reports

20 Minuten said the problem appeared fixed shortly before 20:00 Swiss time. 9to5Mac, which described a widespread outage, put Outlook outage reports on Downdetector at over a hundred thousand for that day, a far higher figure than the snapshot in Fanpage's report. The outlet said its own status checks showed the issue as widespread and ongoing. The figures come from different moments, so they are not directly comparable. Fanpage and Blick gave no time for the outage ending.