Fix Windows 11 KB5065426 Update Error / Install Stuck

The September 2025 Patch Tuesday cumulative update for Windows 11, KB5065426, is proving difficult for many users. Some experience the update stuck at a percentage, others face rollback after reboot, and several encounter error codes like 0x800f081f, 0x800f0922, 0x80070020, or 0xC1900101. This article brings together tested fixes, official Microsoft guidance, and community-sourced solutions so you can safely install this critical update.

Why KB5065426 Matters

Skipping cumulative updates exposes your PC to known vulnerabilities that Microsoft has already patched. KB5065426 addresses security flaws in the kernel, Microsoft Edge components, and networking drivers. It also includes performance improvements for OBS Studio stuttering and fixes to prevent WUSA failures on network shares.

If your device is blocked by a known safeguard hold (e.g., Intel SST audio drivers on certain laptops), Microsoft will list it on the Windows Release Health Dashboard.

Before You Start: Quick Checklist

• Free up at least 10–15GB of disk space (disk cleanup guide).
• Pause third-party antivirus and disconnect USB accessories.
• Ensure a stable wired internet connection.
• Create a restore point: Search “Create a restore point” → Configure → Create.

Step-by-Step Fixes for KB5065426

1) Run the Windows Update Troubleshooter

Windows includes a built-in troubleshooter that resets update services and clears temporary blocks.

2) Clear the Windows Update Cache

1. Press Win + R → type services.msc.
2. Stop the Windows Update service.
3. Navigate to C:\Windows\SoftwareDistribution\Download and delete its contents.
4. Restart the service and reboot.

3) Reset Update Components (Full Reset)

net stop wuauserv
net stop cryptSvc
net stop bits
net stop msiserver
ren C:\Windows\SoftwareDistribution SoftwareDistribution.old
ren C:\Windows\System32\catroot2 Catroot2.old
net start wuauserv
net start cryptSvc
net start bits
net start msiserver

4) Repair System Files (DISM + SFC)

If servicing stack corruption is blocking the update, run:

DISM /Online /Cleanup-Image /RestoreHealth
sfc /scannow

5) Manual Install from Microsoft Update Catalog

If Windows Update continues to fail, download the update directly:
KB5065426 on Microsoft Update Catalog.

6) Safe Mode Update

Driver conflicts (VPN filters, camera drivers, audio devices) can block updates. Reboot into Safe Mode with Networking and rerun the update or installer.

7) In-Place Upgrade (Repair Install)

Use the Windows 11 Media Creation Tool → Upgrade this PC now. This refreshes system files while retaining apps and settings.

Error Codes & What They Mean

• 0x800f081f — Missing system files. Fix: DISM + SFC.
• 0x800f0922 — Recovery/EFI partition issues. Free space or repair partitions.
• 0x80070020 — File in use. Pause antivirus, close sync tools.
• 0x80242016 — General install failure. Reset update components.
• 0xC1900101 — Driver error. Update/rollback drivers or use Safe Mode.

New Issues Reported Since Initial Publication

• WUSA failures from network shares (ERROR_BAD_PATHNAME).
• OBS Studio stutter fix confirmed in this cumulative update.
• Some users required a Windows activation check post-reboot.

Real-World Example

One reader with repeated 0x800f081f errors fixed it by:

1. Running DISM /RestoreHealth.
2. Running sfc /scannow.
3. Manually installing via Update Catalog.

Takeaway: Always restore servicing health before retrying.

Prevention Tips for Future Updates

• Maintain 10–15GB free space before Patch Tuesday.
• Update chipset, GPU, and NIC drivers monthly.
• Pause antivirus only during installation.
• Prefer Ethernet over Wi-Fi for large updates.
• Backup BitLocker recovery keys.

Frequently Asked Questions