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Patch intelligence record
Windows 11 25H2 (Build 26200.9457)
Evidence summary: Negative
25 user reports found
AUXSAYS verdict
WAIT
Current reports mention update/install failure, boot failure, and bsod / stop error. This page covers one cumulative update, not the whole 25H2 servicing train; reports about a later update are counted on that update's own page.
Recommendations
- Pause updates if this machine is doing deadline-sensitive or production work.
- Check Microsoft's known-issue and safeguard-hold list for this KB before installing.
- Keep the uninstall path in mind: a cumulative update can be removed from Settings > Windows Update > Update history for a limited window after installation.
Current reports mention update/install failure in windows update, boot failure in startup / boot, bsod / stop error in system stability.
Community monitoring
MONITORING ACTIVE
- Accepted reports
- 25
- Latest evidence run
- Oct 6, 2026
- Healthy sources
- 2 fresh (success / no reports) · need 2
- Microsoft Q&A (search) Completed last checked Oct 6, 2026
- techcommunity windows sitemap Checked — no reports found last checked Oct 6, 2026
Monitoring reflects community-evidence collection health for this exact release — an absence of reports is not a safety guarantee, and this is separate from the AUXSAYS verdict.
Vendor Known Issues — 2 active vendor-known issues
2 active 7 resolved
Official vendor Release Health status. Not counted as community reports. Official source ↗
Official Patch Notes — vendor release notes captured from the official source
Windows 11 25H2 cumulative update, OS build 26200.9457 (KB5129195). Released 2026-09-14 on the General Availability Channel. Update type 2026-09 OOB. This is the official Microsoft Windows release-health entry (learn.microsoft.com/windows/release-health). Known-issue and safeguard-hold details are published on the per-version Windows release-health status page. Microsoft Release Health status (official) for Windows.
Windows 11 in these notes: .
Windows 11 25H2 cumulative update, OS build 26200.9457 (KB5129195). Released 2026-09-14 on the General Availability Channel. Update type 2026-09 OOB. This is the official Microsoft Windows release-health entry (learn.microsoft.com/windows/release-health). Known-issue and safeguard-hold details are published on the per-version Windows release-health status page.
Technical Details
- Released
- Sep 14, 2026
- File size
- Official source checked
- Oct 6, 2026
- Official notes checked
- Oct 6, 2026
Checksum
Use these hashes to verify downloaded installers match the files published with the official release.
User Reports / Sources (25)
User report sources used for the current read.
- Microsoft Learn Q&A. (2026, September 15). Two culprits: Security Update from 9/9, (KB5124008)(26200.9445) and (KB5129195)(26200.9457) installed on 9/15 - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 17). 2026-09 Security Updates failures - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 16). Unable to install Windows Security Update (KB5129195) (26200.9457) - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 16). Update problem - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 18). Windows Security stuck on logo; SecurityHealthService starts then stops, KB5007651 repeatedly reinstalls on Windows 11 25H2 - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 17). Microsoft Store: “You need administrator privileges to pause updates” on Windows 11 Pro 25H2 - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 19). 2026-09 Security Update KB5129195 destroys Windows 11 (omitting screenshot) - Microsoft Q&A. microsoft learn qna Issue: boot failure in startup / boot Workflow: startup / boot
- Microsoft Learn Q&A. (2026, September 18). File History Backup Problems with last security update - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 18). Secure boot violation after installing a few updates - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 20). Windows 11 25H2 – CBS/Component Store inconsistency prevents repair installation and cumulative updates - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 19). Windows Cumulative Updates KB5129195 fail leading to 0x139 KERNEL_SECURITY_CHECK_FAILURE - Microsoft Q&A. microsoft learn qna Issue: bsod / stop error in system stability Workflow: system stability
- Microsoft Learn Q&A. (2026, September 19). Microsoft Store Error 0x80070422 - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 20). DISM /ScanHealth leaks WinSxS\Temp\InFlight data on Windows 11 25H2 Build 26200.9457 - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 23). Started giving me blue/green/black screen. - Microsoft Q&A. microsoft learn qna Issue: boot failure in startup / boot Workflow: startup / boot
- Microsoft Learn Q&A. (2026, September 23). Kernel bugcheck 0x1E (AV_nt!HvpGetCellMap) recurs 3x on build 26100.9457 / 26200.9457, never on the two prior builds - Microsoft Q&A. microsoft learn qna Issue: bsod / stop error in system stability Workflow: system stability
- Microsoft Learn Q&A. (2026, September 22). Aggiornamento della sicurezza (KB5129195) (26200.9457) Errore di installazione - 0x80070002 - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 22). I'm having problems with Windows 11Pro 25H2 26200.9457/Pack 1000.26100.360.0 - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 24). Windows Security App (Microsoft.SecHealthUI) stuck at 1000.26100.1.0 after KB5007651 and SecurityHealthSetup installation - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 25). KB5129195 causes Classic Outlook 2024 to hand - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 27). Windows Update fails with "Something went wrong" — UpdateOrchestrator event log missing even after in-place repair - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 29). Aggiornamento della sicurezza (KB5129195) (26200.9457) Errore di installazione - 0x80070002 - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 30). NCSI problems after the update KB5129195 - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, September 29). Microsoft Print To PDF Problems - Microsoft Q&A. microsoft learn qna Issue: unspecified windows issue in Windows workflow Workflow: Windows workflow
- Microsoft Learn Q&A. (2026, October 1). 2026-09 Security Update (KB5129195) (26200.9457) Failed, update files missing or problems - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
- Microsoft Learn Q&A. (2026, October 6). Need correct Windows 11 25H2/26H2 English International ISO for in-place repair - Microsoft Q&A. microsoft learn qna Issue: update/install failure in windows update Workflow: windows update
Official sources
- Microsoft. (2026, September 14). Windows 11 release information.release health
- Microsoft. (2026, September 14). Windows release health.release health
- Microsoft. Download page.download