Windows Update stalled at 0%, rolled back with an error, or keeps restarting in a loop — these failures are common, but the right fix depends on which part of the process broke down. The root cause could be insufficient free disk space, a corrupted update cache, damaged system files, a network or VPN issue, or a hardware-compatibility block. This guide covers every scenario for Windows 11 (through 24H2) and Windows 10, starting with the quickest checks and working up to manual installs and in-place upgrades.
Table of Contents
- Diagnose first: recognizing the type of failure
- Free up disk space
- Run the Windows Update troubleshooter
- Clear the update cache
- Repair system files with DISM and SFC
- Network, drivers, and security software
- Install updates manually from the Microsoft Update Catalog
- Run an in-place upgrade to repair Windows
- Windows 11-specific failures: TPM 2.0, compatibility blocks, and CPU requirements
- Last resort: reset or reinstall Windows
- Frequently asked questions
- Summary: the best fix for each error code
Diagnose first: recognizing the type of failure
Windows Update failures come in several distinct forms, and the most effective fix varies by symptom and error code. Before trying anything, identify when the process stops and what error, if any, is displayed — that single step can save a lot of time.
Error code quick-reference (0x80070005, 0x80070070, 0x800f081f, 0x80240034, and more)
The table below lists the most common Windows Update error codes, what each one means, and where to start.
| Error code | Primary cause | Recommended first step |
|---|---|---|
| 0x80070005 | Access denied — insufficient permissions | Run as administrator; temporarily disable antivirus software |
| 0x80070070 | Not enough disk space | Free up disk space (see the "Free up disk space" section below) |
| 0x8007000E | Not enough memory | Restart the PC, close unnecessary apps, then try again |
| 0x80070002 | File not found | Clear the update cache; repair system files with SFC |
| 0x80070057 | Invalid parameter | Clear the update cache; repair with DISM |
| 0x800f081f | .NET Framework source files not found | Re-enable the optional feature from Windows Features; or run DISM repair |
| 0x800f0922 | System Reserved partition is full, or active VPN connection | Free space on the System Reserved partition; disconnect from VPN |
| 0x80240034 | Download failed (generic) | Check your network; clear the update cache; try a manual install |
| 0x80248007 | Cannot connect to the Windows Update service | Check your network; restart the Windows Update service |
| 0xC1900101 | Driver compatibility failure (common during feature updates) | Update or remove the incompatible driver, then retry |
| 0x80190001 | HTTP error — unexpected server response | Restart and retry; check VPN and proxy settings |
No error code on screen? You can still narrow things down by symptom.
Symptom guide: restart loops, stalled downloads, install failures, and rollbacks
If no error code appears, match your situation to one of the descriptions below:
- Download stuck at 0% or a specific percentage: Usually a network problem or a corrupted update cache. Clear the cache first.
- Installation freezes or hangs midway: Points to corrupted system files or a driver compatibility issue. Run DISM and SFC.
- "Undoing changes made to your computer" appears and rolls back: An error occurred during installation. Check the Event Viewer for a specific error code, then act on it.
- Restart loop (update → restart → update screen again): Often caused by a corrupted cache or system files. Boot into Safe Mode and clear the cache.
Free up disk space
Insufficient free disk space is one of the most frequent reasons Windows Update fails. Feature updates — such as 22H2, 23H2, or 24H2 — demand significantly more space than monthly quality updates.
How much free space Windows Update needs
Microsoft's recommended minimums vary by update type:
| Update type | Recommended free space |
|---|---|
| Monthly quality update (cumulative update) | At least 2–5 GB |
| Feature update (e.g., 23H2 → 24H2) | 20 GB or more recommended |
| Windows 11 upgrade | 64 GB total storage; at least 20 GB free |
If your C:\ drive has less than 10 GB free, clear space before attempting anything else.
Disk Cleanup and Delivery Optimization cache removal
Windows' built-in Disk Cleanup tool handles the most common sources of wasted space:
- Search for Disk Cleanup in the Start menu and open it.
- Select the C: drive and click OK.
- Check Windows Update Cleanup, Temporary files, and Recycle Bin.
- Click Clean up system files to unlock additional categories — including old Windows installations that can reclaim several gigabytes.
- Click OK, then Delete Files to confirm.
The Delivery Optimization cache — update files your PC has cached to share with other devices on the network — can also grow large over time. To limit or clear it, go to Settings → Windows Update → Advanced options → Delivery Optimization → Advanced options, and adjust the cache size settings there.
DISM component store cleanup and compression
The Windows component store (C:\Windows\WinSxS) accumulates superseded update files and can swell over time. Open an elevated Command Prompt and run:
DISM /Online /Cleanup-Image /StartComponentCleanup
For a more aggressive cleanup, add the /ResetBase flag — but note that this removes the ability to uninstall recent updates, so only use it on a stable system:
DISM /Online /Cleanup-Image /StartComponentCleanup /ResetBase
Run the Windows Update troubleshooter
Windows includes a built-in troubleshooter that automatically detects and fixes common update problems. It's worth running before any manual steps.
Steps for Windows 11
- Open Settings from the Start menu.
- Go to System → Troubleshoot → Other troubleshooters.
- Find Windows Update in the list and click Run.
- The troubleshooter will diagnose and attempt repairs automatically. If prompted to restart when it finishes, do so before trying Windows Update again.
Steps for Windows 10
- Open Settings from the Start menu.
- Go to Update & Security → Troubleshoot → Additional troubleshooters.
- Click Windows Update, then click Run the troubleshooter.
What to check after it finishes
If the troubleshooter reports "Fixed" or "Changes were made," restart your PC and run Windows Update again. If it says "No issues found" or the update still fails, move on to clearing the update cache.
Clear the update cache
When Windows Update stalls or repeats the same error, a corrupted cache is often the culprit. Deleting the cached files forces Windows to download fresh copies, which resolves the issue in many cases.
Stop the Windows Update services
You need to stop the relevant services before touching the cache folders. Open Command Prompt (as administrator) and run each command in order:
net stop wuauserv
net stop cryptSvc
net stop bits
net stop msiserver
Each command should return "The service was stopped successfully."
Delete the SoftwareDistribution and catroot2 folders
With the services stopped, clear the contents of the following folders. Delete the files inside each folder — do not delete the folders themselves.
- In File Explorer, open C:\Windows\SoftwareDistribution and delete everything inside it.
- Do the same for C:\Windows\System32\catroot2.
Alternatively, rename the folders from the command prompt — Windows will create fresh replacements automatically:
ren C:\Windows\SoftwareDistribution SoftwareDistribution.old
ren C:\Windows\System32\catroot2 catroot2.old
Renaming keeps the old files as a backup in case you need to refer to them later.
Restart the services and try again
Once the folders are cleared, restart the services:
net start wuauserv
net start cryptSvc
net start bits
net start msiserver
Restart your PC, then open Windows Update and try again. If a corrupted cache was the problem, the update should now complete.
Repair system files with DISM and SFC
If clearing the cache doesn't help, corrupted system files may be preventing the update from completing. Windows includes two tools for detecting and fixing this: DISM and SFC.
Repair the Windows image with DISM
DISM (Deployment Image Servicing and Management) repairs the Windows image itself by downloading replacement files directly from Microsoft's servers. An internet connection is required, and the process can take 10–30 minutes. Open Command Prompt (as administrator) and run:
DISM /Online /Cleanup-Image /CheckHealth
If that detects problems, follow up with:
DISM /Online /Cleanup-Image /ScanHealth
DISM /Online /Cleanup-Image /RestoreHealth
RestoreHealth downloads and replaces corrupted components. Wait for it to finish — "The operation completed successfully" confirms it worked.
Run the System File Checker (SFC)
SFC scans Windows system files and replaces any that are damaged. Run it from an elevated Command Prompt:
sfc /scannow
The scan takes a few minutes to about 15 minutes. When it finishes, you'll see one of the following messages:
- "Windows Resource Protection did not find any integrity violations" — system files are fine
- "Windows Resource Protection found corrupt files and successfully repaired them" — repair complete; restart and retry Windows Update
- "Windows Resource Protection found corrupt files but was unable to fix some of them" — run DISM RestoreHealth first, then rerun SFC
Recommended order and things to watch out for
Always run DISM before SFC. DISM restores the Windows image to a healthy baseline, and SFC then uses that clean image as a reference when replacing damaged files. After running both tools, restart your PC before attempting Windows Update again.
Network, drivers, and security software
Even with a healthy system and plenty of disk space, network settings, antivirus software, or outdated drivers can silently block Windows Update.
VPN and proxy interference
VPN software and manual proxy settings can disrupt the HTTPS connection that Windows Update needs to reach Microsoft's servers. Error codes 0x800f0922 and 0x80190001 are common indicators of VPN-related failures.
- Disconnect from your VPN and try running Windows Update again.
- In Settings → Network & Internet → Proxy, check whether a manual proxy is configured and disable it.
- If you suspect a DNS issue, run netsh winsock reset in an elevated Command Prompt and restart.
Antivirus software blocking updates
Third-party antivirus programs (AVG, Avast, Kaspersky, and others) can intercept Windows Update downloads or block writes to system folders. If 0x80070005 (Access denied) keeps appearing, antivirus interference is a likely cause.
Temporarily disable real-time protection in your antivirus settings, run Windows Update, then re-enable protection once the update is complete. If you're comfortable doing so, a full uninstall followed by reinstall after the update is the most reliable test — just don't forget to reinstall it afterward.
Outdated driver compatibility issues
Feature updates — such as upgrading from Windows 11 22H2 to 23H2 — can fail when an old device driver is incompatible with the new version of Windows. Error code 0xC1900101 almost always points to a driver problem.
- Open Device Manager and look for any devices flagged with a yellow ! warning icon.
- Prioritize updating your graphics driver, chipset driver, and network adapter driver.
- If you're running a beta or unofficial driver, rolling back to the stable release may fix the block.
Install updates manually from the Microsoft Update Catalog
When a specific update keeps failing — and you know its KB number from the update history or error log — you can download and install it directly from the Microsoft Update Catalog, bypassing the automated Windows Update process entirely.
How to use the Microsoft Update Catalog
- Open catalog.update.microsoft.com in your browser.
- Find the KB number of the failing update from Windows Update history or an error log (for example, KB5034441).
- Search for that KB number on the Catalog site.
- From the results, download the package that matches your OS and architecture — x64 for most PCs, or ARM64 for Snapdragon-based devices.
Installing an .msu file with the wusa command
Double-clicking the downloaded .msu file will launch the installer, but running it from an elevated Command Prompt lets you see any error output:
wusa C:\Users\YourUsername\Downloads\filename.msu /quiet /norestart
After the installation finishes, restart your PC. The update should then appear as installed in Windows Update history.
Run an in-place upgrade to repair Windows
If you've worked through everything above and Windows Update still won't cooperate, an in-place upgrade (also called a repair install) is the next step. It reinstalls Windows on top of itself, replacing system files and fixing deep-seated issues — while keeping your personal files, applications, and settings intact.
Download the Media Creation Tool
- From Microsoft's Windows download page, download the Media Creation Tool for your version of Windows (Windows 11 and Windows 10 have separate tools).
- Run the tool and select Upgrade this PC now — you don't need to create an ISO or USB drive.
Run the upgrade and keep your files
- When setup launches, choose Upgrade now.
- After Windows checks for the latest updates, you'll reach the install options screen. Make sure to select Keep personal files and apps.
- Click Install to begin the repair install.
Time required and things to keep in mind
An in-place upgrade typically takes one to three hours, depending on your hardware. Do not turn off the PC during the process. If you're on a laptop, plug in the power adapter before you start. The PC will restart automatically when finished, and you'll boot back into a repaired copy of Windows with your files and apps intact — though some drivers may be reinstalled.
Windows 11-specific failures: TPM 2.0, compatibility blocks, and CPU requirements
Windows 11 enforces stricter hardware requirements than Windows 10. When those requirements aren't met — or when Microsoft has placed a targeted block on a specific PC configuration — feature updates simply won't install.
Checking TPM 2.0 and Secure Boot
Windows 11 feature updates require TPM 2.0 and Secure Boot to be active. Here's how to verify each:
- TPM status: Press Win + R, type tpm.msc, and press Enter. The window should read "The TPM is ready for use" with Specification Version: 2.0.
- Secure Boot status: Press Win + R, type msinfo32, and press Enter. Look for the "Secure Boot State" row — it should say "On." Alternatively, go to Settings → System → Recovery → Advanced startup → Restart now, then Troubleshoot → Advanced options → UEFI Firmware Settings to check your BIOS directly.
If TPM 2.0 isn't detected, you may need to enable it in your BIOS — look for settings labeled PTT (Intel), fTPM, or AMD fTPM, depending on your hardware.
Compatibility holds and 24H2 known issues
Microsoft occasionally places safeguard holds on specific PCs to prevent updates that are known to cause problems on certain hardware or software configurations. If your PC is under a hold, the update simply won't appear, or you may see a message like "We're making sure your device is ready for Windows 11."
- Windows 11 24H2 is known to cause BSODs on PCs with older versions of the Intel Smart Sound Technology (SST) driver. Affected PCs are blocked from receiving 24H2 until the driver is updated or removed.
- Older versions of certain disk-partitioning tools (such as DiskGenius) have also triggered compatibility holds.
The safest approach is to update or remove the flagged app or driver, then check Windows Update again. If no specific issue is identified, the hold may lift on its own after Microsoft resolves the underlying problem.
Last resort: reset or reinstall Windows
When nothing else has worked, resetting Windows brings the system back to a clean, working state. This is the option of last resort — but it reliably resolves even the most stubborn update failures.
Reset this PC and keep your files
Windows can reinstall itself while preserving your personal files (documents, photos, and so on). Apps and settings will be removed, but your data in user folders is kept.
- Go to Settings → System → Recovery (Windows 11) or Settings → Update & Security → Recovery (Windows 10).
- Click Reset this PC, then Get started.
- Choose Keep my files.
- Follow the on-screen instructions. The process takes one to two hours.
Clean install for a completely fresh start
For the most thorough result, create a bootable USB drive using the Media Creation Tool and perform a clean install. A clean install erases all files, applications, and settings, so back up anything important before you begin.
When the Windows Setup wizard asks where to install Windows, click Drive options (advanced) and delete the existing partition before installing. This gives you a completely blank slate and removes any lingering driver or configuration problems.
Frequently asked questions
Download stuck at 0% or a specific percentage?
If the download hasn't moved for several hours, restart the PC and open Windows Update again. If it stalls again, clear the update cache by deleting the contents of the SoftwareDistribution folder (see the cache-clearing section above). Also open services.msc and confirm that the Windows Update service is set to start Automatically.
Stuck in a restart loop during the update?
Boot into Safe Mode and clear the update cache from there. To enter Safe Mode, hold Shift and click Restart on the sign-in screen, then choose Troubleshoot → Advanced options → Startup Settings → Restart → Safe Mode with Networking. If you can't reach Safe Mode normally, boot from Windows installation media and use Startup Repair. If the loop continues after that, an in-place upgrade or a reset is the next step.
"Undoing changes made to your computer" appears every time?
A repeated rollback means the installation is failing partway through. Open Event Viewer (eventvwr.msc), go to Windows Logs → System, and look for errors around the time the update ran. Once you have an error code, match it to the quick-reference table at the top of this guide. If a specific KB is responsible, you can either hide it temporarily using the Show or Hide Updates tool, or install it manually from the Microsoft Update Catalog.
One specific update keeps failing?
Download that KB directly from catalog.update.microsoft.com and install it manually using wusa. If the manual install also fails, run DISM and SFC to repair system files, then try again.
Summary: the best fix for each error code
When Windows Update fails, identify the error code or symptom first, then work through the fixes in the order shown below.
| Situation / error code | First step | If that doesn't work |
|---|---|---|
| Insufficient disk space (0x80070070) | Run Disk Cleanup; delete unnecessary files | DISM component store cleanup |
| Access denied (0x80070005) | Run as administrator; disable antivirus temporarily | Clear the update cache |
| Download failed (0x80240034) | Check network and VPN; clear the cache | Manual install from the Update Catalog |
| Driver compatibility (0xC1900101) | Update or remove the problematic driver | In-place upgrade |
| Corrupted system files | DISM repair → SFC scan | In-place upgrade |
| Repeated rollback | Clear cache → DISM/SFC | Manual install → Reset |
| Restart loop | Boot into Safe Mode; clear the cache | Startup Repair → Reset |
| Windows 11 feature update not offered | Verify TPM 2.0 and Secure Boot | Wait for the compatibility hold to lift, or update/remove the flagged driver |
Most Windows Update failures trace back to one of a handful of causes. Working through them in order — free up disk space → troubleshooter → clear cache → DISM/SFC → manual install → in-place upgrade — resolves the vast majority of cases. Only consider a reset or clean reinstall if everything else has failed.
For other Windows troubleshooting topics, see the Windows Troubleshooting Guide | Solutions by Symptom.
