Microsoft acknowledged "an issue impacting users attempting to access Exchange Online or functionality within Microsoft Teams calendar" earlier in the day. In updates posted on X, the social media platform formerly known as Twitter, the company's status page said it identified a "recent change" that it believed to be behind the problem — and was working to revert it.
Microsoft shared that it was deploying a fix — which, as of shortly before noon E.T., it said had reached about 98% of "affected environments."
Still, the company's status page later added, targeted restarts were "progressing slower than anticipated for the majority of affected users."
As of midday Monday, Downdetector showed thousands of outage reports from users of Microsoft 365, particularly Outlook.