Microsoft resolves Teams and Outlook launch failures on ARM Windows devices
Fix addresses post-Patch Tuesday bug affecting ARM-based Windows PCs

Key Takeaways
- Microsoft has fixed a bug causing Teams and Outlook to fail on ARM Windows devices.
- The issue was triggered by updates released since the August 2026 Patch Tuesday.
- No security exploitation has been reported; it is a functional bug.
- Affected users should install the latest Microsoft updates to resolve the problem.
Quick answers
- What happened?
- Microsoft has fixed a bug that prevented Microsoft Teams and Outlook from launching on ARM-based Windows devices after installing updates released since the August 2026 Patch Tuesday. The issue disrupted productivity for affected users, but no security exploitation has been reported.
- Which products are affected?
- Microsoft Teams, Microsoft Outlook, Windows on ARM
- What should defenders do?
- Install the latest Microsoft updates to apply the fix. If the issue persists, verify that all pending updates are installed and consider contacting Microsoft support for further assistance.
Microsoft has released a fix for a known issue that caused Microsoft Teams and Outlook to fail to launch on ARM-based Windows devices. According to a report from BleepingComputer, the problem occurred after users installed updates released since the August 2026 Patch Tuesday. The bug affected ARM versions of Windows, preventing the two productivity applications from starting normally.
The exact root cause has not been disclosed, but Microsoft has now addressed the issue. The fix is expected to restore normal functionality for affected users. No CVE identifiers have been associated with this bug, and there is no indication that it was exploited in the wild. This appears to be a functional defect rather than a security vulnerability.
Organizations using ARM-based Windows devices, such as those powered by Qualcomm Snapdragon processors, should ensure that the latest updates from Microsoft are installed to resolve the launch failures. Users who continue to experience issues are advised to check for pending updates or contact Microsoft support.
While this incident does not pose a direct security risk, it highlights the importance of timely patch management and the potential for update-related disruptions in enterprise environments.
Security Details
This is a functional bug, not a security vulnerability. No CVE IDs have been assigned, and no exploitation has been reported. The impact is limited to application launch failures on ARM-based Windows devices.
Affected products
Microsoft Teams, Microsoft Outlook, Windows on ARM
Mitigation
Install the latest Microsoft updates to apply the fix. If the issue persists, verify that all pending updates are installed and consider contacting Microsoft support for further assistance.
Sources
BleepingComputer
Microsoft fixes Teams, Outlook launch failures on ARM Windows PCs
Sep 11, 2026 · 09:39
Original link
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