KB5124010 took many of my PCs to build 26200.9550 last night. So far, no new issues or gotchas to report, including no Secure Boot changes. Been an interesting month for updates! #WindowsInsiders #MVPbuzz support.microsoft.com/en-us/servic...
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September 22, 2026—KB5124010 (OS Builds 26200.9550 and 26100.9550) Preview | Microsoft Support
September 22, 2026—KB5124010 (OS Builds 26200.9550 and 26100.9550) Preview