Tens of thousands of users were unable to access various Microsoft programs on Saturday afternoon.

“We’re investigating an issue in which users may be unable to access Outlook features and services,” Microsoft 365 Status, the official Microsoft account for 365 service incidents, said in a post on X. “Additional details can be found under MO1020913 in the admin center.”

The number of reports that services such as Microsoft Outlook, Microsoft Exchange, Microsoft Teams, Microsoft 365 and Microsoft Azure were down spiked after 3:30 p.m. ET. More than 37,000 individuals reported an Outlook outage and roughly 24,00 reported an outage in the tech company’s 365 service, according to Downdetector, while roughly 150 users reported their Teams accounts were down.

The outages were most highly concentrated in the New York, Chicago and Los Angeles areas, per the Downdetector reports.

Users also flooded social media site X complaining about their inability to access their Outlook emails, prompting concerns of a global Microsoft outage.

Microsoft has not reported any issues on its service health update page, and the company has not responded to a request for comment.

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