Microsoft outage drags into second day; Outlook and Teams still spotty

Where recovery stands: At 3:11 a.m. PT Friday, Microsoft said traffic was being gradually restored and that it was seeing improvements in mailbox access and delayed email processing, "though some intermittent issues may continue." It said clearing email backlogs is a priority and that an extended 48-hour email timeout window remains in place to protect delayed messages, The Independent reported.

How big: Downdetector showed about 130,000 reports of Outlook problems at the peak Thursday, and more than 47,000 for Microsoft 365, USA Today reported. Reports came from 74 countries and territories. By about 3 a.m. PT Friday, Outlook reports were down to around 15,000. Those are user-submitted reports, so the real number of people affected is not known.

What Microsoft says caused it: The company first blamed "elevated load," then said it was "not driven by an increase in traffic, but by a number of servers being unexpectedly unavailable." Late Thursday it said changes meant to improve service had not taken "as expected," USA Today reported. Microsoft executive Charles Lamanna said the outage did not appear to be a cyberattack, and the company said it has "no evidence of malicious activity," The Independent reported. Microsoft has promised a post-incident report with the root cause after recovery.

Timeline (PT): Thursday about 10 a.m., outage begins and reports spike. About 1 p.m., Microsoft says an alternative health check returned some servers to service. About 4 p.m., some returned servers fail again under traffic and Microsoft begins rebuilding servers with an older configuration. About 7:30 p.m., Microsoft says its latest changes did not work as expected. Friday 2:28 a.m., recovery "progressing in phases." 3:11 a.m., traffic gradually restored, with intermittent issues.

What's still unknown: Microsoft has not said what made the servers fail, how many customers lost access, or when service will be fully restored. Businesses that rely on Microsoft 365 should watch the status page for the all-clear and expect delayed emails to keep arriving.

Times are converted to Pacific time from Microsoft's posted updates and from times given by CNBC, BBC, USA Today and The Guardian. Downdetector counts are user-submitted reports, not a measure of how many people were affected. Microsoft had not named a final root cause or declared full recovery as of its update around 3:11 a.m. PT on Nov. 13. Photo is a file image of Microsoft's Redmond, Washington, campus (2022), not from this event.