Exchange Online outage is a warning against IT monocultures. The most recent Microsoft Exchange Online outage ( event code EX1464935 ) has been confirmed by Microsoft.
On August 31, late Monday afternoon, Exchange Online went down – and with it Teams, SharePoint, Purview, Defender XDR and several others. Tens of thousands of companies were suddenly unable to communicate and, in some cases, function.
The cause wasn’t a major orchestrated attack or a natural disaster, but according to Microsoft, an “authentication component issue.” Rumors later circulated online that it was simply an expired certificate. It can happen to even the best of families.
In fact, this outage mainly shows how vulnerable modern IT infrastructure is when too much is in the hands of one provider. It's extremely convenient for users, but also for administrators: Microsoft provides mail and chat, identity, collaboration, file storage and security, all tightly connected through a single sign-on and included in a corporate subscription. However, an authentication error at Microsoft can plunge half the company into the void.
Digital sovereignty is currently being discussed mainly politically as a question of data center location, contractual clauses and the development of strong European AI models. But August 31st shows that a dominant is one who can keep working when another provider fails. A dominant is one who can threaten to leave at the next price increase.
This assumes that one has functional alternatives. The state of Schleswig-Holstein , but also many other companies and organizations, have proven that this is possible. Of course, the Nextcloud , Open-Xchange and Rocket.Chat installations can also go down. But they won't all go down at the same time on a Monday afternoon. And if you manage them yourself, you can fix the error yourself instead of waiting for Microsoft.
Of course, this is not as convenient as an M365 subscription. You need a second, technically independent communication channel, which you also need to use occasionally, so that it works reliably in case of an emergency. You need to store emergency documents in a way that they are accessible even in the event of an IT failure. You need to think about exit scenarios and data portability. You need to investigate and document where there are risks because too many functions come from a single provider – and how to address them. And you need to ensure diversity in the software landscape, even if switching between different tools is not as comfortable as an all-in-one solution.
A few days after the outage, the Exchange Online issues have been resolved. Microsoft will publish a report detailing the causes of the outage and the consequences that resulted from it. However, it would be more important for the companies affected to draw their own conclusions and ask themselves: How much of our processes depend on individual providers? What will happen if they go down? How can we protect ourselves from this?
Although the press releases will range from very select to rare, I said I'd pass...because sometimes the editors hide.
