March 2026: Users may intermittently be unable to join meetings or access Microsoft Teams Free for Windows
A recent Windows update introduced a regression that caused Microsoft Teams Free users on Windows to intermittently be unable to join meetings or access the service, with users seeing authentication error messages stating "We couldn't authenticate you" due to device, network, or technical issues. The incident affected multiple Windows versions (25H2, 24H2, 23H2, and 22H2) and lasted 47.3 hours while Microsoft developed a fix to address the regression. Users could temporarily resolve the issue by restarting their computers as a workaround during the incident.