Microsoft Teams on Office 365, a service that passed the 20 million user mark late last year, was knocked down this morning by a certificate issue. Specifically, an authentication certificate was allowed to expire, keeping millions from logging in to the service.
Microsoft acknowledged the service interruption at approximately 9:15 a.m., ET and by roughly 10:30 a.m. ET it had acknowledged that the problem was certificate based. An hour later, the company tweeted that it had begun the remediation process, with a message at nearly 5:00 p.m. ET that the fix had been applied.
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