Microsoft Teams obviously weren’t expecting what happened this morning, as they went down for a few hours, and it seems that a pretty rookie mistake is to blame.
Microsoft somehow forgot to renew the SSL certificate on their site, which guarantees a secure connection between a web browser and a web server.
With that, the app told users that it failed to establish an HTTPS connection to Microsoft’s servers.
We’ve determined that an authentication certificate has expired causing, users to have issues using the service. We’re developing a fix to apply a new certificate to the service which will remediate impact. Further updates can be found under TM202916 in the admin center.
— Microsoft 365 Status (@MSFT365Status) February 3, 2020
It’s quite odd for a big company like Microsoft Teams to forget to renew something as important as authentication certificate, and it was rude timing, as so many were attempting to log in and start their week.
Almost three years old, Microsoft Teams is the company’s Slack competitor. Last year, it added new features like private channels and custom video chat backgrounds, and it recently launched its first TV ad campaign. There would be no need to say, today’s problem probably doesn’t help in Microsoft’s efforts to take on Slack.