Windows 11 23H2 build 22621.9334 (KB5087058) — release notes, downloads, known issues

Windows 11 · 23H2 · .NET Framework update

Cumulative Update for .NET Framework for Windows 11, version 23H2 - KB5087058 (22621.9334)

Windows 11 23H2: Home/Pro servicing ended November 2025

This is a .NET Framework package for Windows 11 23H2, not an operating-system build. Its history below lists other .NET packages on the 22621 base.

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Issue KB5087420 BitLocker Recovery Key Warning After Secure Boot Migration (Win 11 23H2) May 12, 2026 · Windows 11 23H2 coverage from this build's release window
Coverage Microsoft 2026 End of Support: Windows 11 24H2/23H2 and Office 2021 Deadlines May 11, 2026 · Windows 11 23H2 coverage from this build's release window
Issue Windows Autopatch EU Driver Bug Installs Without Manual Approval (23H2–25H2) May 14, 2026 · Windows 11 23H2 coverage from this build's release window
Coverage KB5094156 (June 9, 2026): Safe OS Update and Secure Boot Cert Expiration for Win 11 23H2 Jun 9, 2026 · Windows 11 23H2 coverage from this build's release window
Coverage KB5095971 Setup Dynamic Update: Improve Windows 11 23H2 Feature Update Reliability Jun 9, 2026 · Windows 11 23H2 coverage from this build's release window
Fix KB5093998 Windows 11 23H2 Secure Boot & BitLocker Fixes: What IT Must Know Jun 9, 2026 · Windows 11 23H2 coverage from this build's release window
Coverage Windows 11 26H2: 174KB Enablement for 24H2/25H2, 6.5GB for 23H2 Jun 26, 2026 · Windows 11 23H2 coverage from this build's release window

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