UPDATE with the latest version: Microsoft’s latest release says that “targeted restarts are progressing slower than expected for the majority of affected users” after an outage due to an unspecified “recent change” crippled Microsoft 360, Outlook, Exchange and more.

An estimated time of arrival (ETA) for the solution will be provided by Microsoft when it becomes available, the tech giant said.

PREVIOUSLY: A massive outage at Microsoft on Monday crippled Microsoft 365, impacting global users of Teams, Outlook and Exchange email, calendars and more.

The Downdector website showed reports of outages that grew overnight into a huge spike that began around 8 a.m. ET this morning and included up to 4,350 complaints, most of them around Exchange. Microsoft has updates available all morning

The tech giant said it has “begun deploying a fix” and is now “initiating manual restarts on a subset of machines that are in an unhealthy state.”

As of noon ET, it said the fix had reached about “98% of our affected environments.”

Today’s problems follow a collapse in July after a corrupt update from a cybersecurity firm called CrowdStrike crashed systems and computers around the world running Microsoft Windows, including banks, airlines, trains, health systems and other industries. A fix then also required a manual restart of the devices.

Microsoft hasn’t said what the “change” it identified today was that caused the problems.