Windows 11 25H2 Upgrade 0x800f0993 PSFX_E_REBASE Fix June 2026

What is the Windows 11 25H2 Upgrade-Path Install Failure?

Since early June 2026, a subset of Windows 11 machines refuse the latest cumulative updates (notably KB5094126 and KB5095149) with the error 0x800f0993 or 0x80073712. The CBS log resolves these to PSFX_E_REBASE_HYDRATION_CANDIDATES_MISSING and ERROR_SXS_COMPONENT_STORE_CORRUPT. The pattern is upgrade-path specific: clean 25H2 installs almost never see it, but devices that walked the 23H2 → 24H2 → 25H2 ladder do. Microsoft acknowledged the issue on June 7, 2026 and pushed a service-side mitigation on May 19, 2026 that fixes most cases without user action — but stale component stores still need a manual nudge.

When does it occur?

• Windows Update downloads to 100% then rolls back at 33% / 65% / 87%
• wusa.exe install with an offline .msu fails with 0x800f0993
• DISM /Add-Package returns 0x80073712 on the same KB
• The error first appeared after the June 2026 Patch Tuesday cycle
• Recently affected: HP EliteBook, Lenovo ThinkPad, Surface Pro 9/10 lines

Common causes

• Orphaned component-store manifests left over from the 23H2 → 24H2 in-place upgrade
• WinSxS rebase hydration candidates were never written during the 24H2 setup
• A truncated pending.xml blocking the servicing stack from completing
• SoftwareDistribution\Download cache containing a partial 25H2 payload
• Corrupted CBS catalog after a previous failed update rollback
• Third-party AV (notably Trellix, SentinelOne agents) locking files during staging
• BitLocker auto-resume mismatch when the TPM was reset between feature updates

Step-by-step fixes

1. Identify your upgrade path first. Run winver and check the build. If you see 26200.xxxx (25H2) AND systeminfo | findstr /B /C:"OS Version" shows a setup history with multiple Installation entries, you are on the broken path. Skip to step 3.
2. Clean 25H2 install path? If you installed 25H2 fresh, this error is almost never yours. Run sfc /scannow followed by DISM /Online /Cleanup-Image /RestoreHealth and retry Windows Update — the May 19, 2026 service mitigation should auto-apply.
3. Stop the servicing stack and purge the cache. In an elevated PowerShell:

   net stop wuauserv
   net stop bits
   net stop cryptsvc
   net stop msiserver
   Remove-Item -Recurse -Force C:\Windows\SoftwareDistribution\Download
   Remove-Item -Recurse -Force C:\Windows\System32\catroot2
   net start cryptsvc; net start msiserver; net start bits; net start wuauserv

1. Remove the half-applied package that is blocking the rebase. Find it with dism /online /get-packages | findstr "KB50941" then remove it with dism /online /remove-package /packagename:Package_for_RollupFix~31bf3856ad364e35~amd64~~26200.XXXX.1.10 (use the exact name from the prior command). Reboot.
2. Rebuild the component store offline. Mount your install media or download the 25H2 ISO. Run DISM /Online /Cleanup-Image /RestoreHealth /Source:WIM:D:\sources\install.wim:1 /LimitAccess substituting D: for your mounted ISO drive letter.
3. Clear pending.xml manually if the servicing stack is still wedged. Boot into WinRE > Command Prompt and run del C:\Windows\WinSxS\pending.xml then dism /image:C:\ /cleanup-image /revertpendingactions. Reboot back into Windows.
4. Reinstall with the standalone MSU. Download the Microsoft Update Catalog version of the failing KB (KB5094126 or KB5095149), then install with wusa.exe path\to\update.msu /quiet /norestart /log:C:\Logs\kb.evtx so you get a usable log if it fails again.
5. Last resort: in-place repair install. Run setup.exe from the 25H2 ISO and choose "Keep personal files and apps". This re-seeds the entire component store without losing data, then run Windows Update — KB5094126 and KB5095149 should install cleanly afterward.

If it still doesn't work

If you've already done the repair install and the update still fails, the most likely culprit is a third-party security agent holding handles on C:\Windows\WinSxS\Manifests\. Boot into Safe Mode with Networking and retry the install — if it succeeds there, uninstall and re-enroll the agent after patching. Enterprise admins should pull the CBS.log (C:\Windows\Logs\CBS\CBS.log) and search for the line immediately preceding the 0x800f0993 to identify the specific missing manifest, then file with Microsoft via the Premier portal referencing the May 19, 2026 mitigation as the suggested fix scope. Bookmark the related [KB5094126 0x80073712 guide](/en/errors/windows-11-kb5094126-june-2026-install-error-0x80073712) and the [KB5095149 install issues roundup](/en/errors/windows-11-kb5095149-june-2026-install-issues) — they cover the adjacent failure modes you may hit next cycle.