Tech article
Microsoft shares workaround for Windows domain login issues - BleepingComputer
Publisher description: Microsoft shared a temporary fix on Wednesday for a known issue that prevents Windows 11 users from logging in with valid domain credentials after installing the September 2026 security updates.
NewsAPI | Sep 17, 2026 | Sergiu Gatlan
Automated excerpt
Admins who investigated this issue have linked the failures to the Machine Identity Isolation Windows security mechanism, which is being set to enforcement mode after this month's KB5124008 (Windows 11 24H2/25H2) or KB5124012 (Windows 11 26H1) updates are installed. On Wednesday, Microsoft confirmed that these authentication issues are triggered by the September 2026 security updates that enable Machine Identity Isolation, causing domain trust failures and sign-in issues with valid domain credentials. After you disable Machine Identity Isolation, restart the device. 4.
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