Microsoft Reverts Teams Update After Desktop Client Launch Failures
Microsoft reverted a service update after it caused some Microsoft Teams desktop client users to become stuck on the loading screen with the error, “We’re having trouble loading your message. Try refreshing.” The company tracked the disruption as incident TM1283300, initially describing it as a transient service infrastructure issue before identifying the root cause as a regression in the Teams client build-caching system that pushed some older desktop builds into an unhealthy state.
Microsoft said the impact appears limited to the desktop client, with no indication that web or mobile users were affected. The company reported that its automated recovery system helped remediate the issue, then fully rolled back the problematic update and monitored telemetry and customer feedback to confirm recovery. Impacted users were instructed to fully quit and restart Teams so the reverted configuration could propagate, though Microsoft did not disclose how many customers or regions were affected.
Timeline
Apr 20, 2026
Microsoft reverts problematic Teams update and issues restart guidance
Microsoft fully reverted the service update responsible for the launch failures and monitored telemetry and customer feedback to confirm recovery. The company instructed impacted users to fully quit and restart the Teams desktop client so the reverted configuration could propagate.
Apr 20, 2026
Microsoft identifies issue and begins automated remediation
Microsoft initially attributed the problem to a transient service infrastructure issue and said its automated recovery system was remediating affected clients. The company classified the event as an incident, indicating noticeable customer impact.
Apr 20, 2026
Teams service update causes desktop client launch failures
A recent Microsoft Teams service update introduced a regression in the client build-caching system, pushing some older desktop client builds into an unhealthy state. Affected users were unable to launch Teams, became stuck on a loading screen, and saw an error message; Microsoft tracked the issue as incident TM1283300.
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