OUTAGE ANALYSIS
AWS Outage: October 20, 2025

The Internet Report

Ep. 36: Microsoft Teams Outage Highlights Need to See Beyond App Front Door

By Angelique Medina
| April 28, 2021 | 2 min read
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Summary

We’re joined this week by Hans Ashlock, Director of Technology & Innovation at ThousandEyes, to discuss the April 27th Microsoft Teams outage.


This is The Internet Report, where we uncover what’s working and what’s breaking on the Internet—and why. We’re joined this week by Hans Ashlock, Director of Technology & Innovation at ThousandEyes, to discuss Tuesday’s Microsoft Teams outage. On Tuesday, April 27th, ThousandEyes tests began to detect an outage affecting the Teams service starting around 3 AM (PT) and lasting approximately 1.5 hours. While the outage occurred in the overnight hours for much of the Americas, the global nature of the outage resulted in service disruption for users connecting from Asia and Europe. 

Transaction views within the ThousandEyes platform show that Microsoft’s authentication service appeared to be available, however, the Teams application was unable to initialize, resulting in error responses. Watch this week’s episode to hear more about what ThousandEyes revealed about the nature of this outage—and what we can all learn from the incident.

Explore this outage for yourself using our interactive ShareLink.


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