Windows Update error 0x80073701

Your Windows Update gets stuck mid-installation with error 0x80073701. It tries again later, fails the same way, and you're wondering if you need to reinstall the whole system. The real answer: almost certainly not. This error sits in the 'fixable' category with some straightforward command-line repairs.

What Causes Windows Update Error 0x80073701?

Error 0x80073701 is a component assembly failure. When Windows tries to install an update, it needs to replace or modify existing files and system assemblies stored in the component store (the WinSxS folder, if you're curious). Sometimes those assemblies are corrupt, superseded versions are tangled up, or the update's metadata is confused about what's actually installed. The update mechanism gives up and throws this error.

The component store corruption usually comes from one of these scenarios. Your system might have crashed mid-update years ago and never fully cleaned up the debris. A security tool or optimization software might have meddled with Windows system folders. You could be low on disk space, which means Windows can't properly stage the update files before installing them. Or you're on a managed network with WSUS (Windows Server Update Services) and the update hasn't been approved or synced correctly on your organisation's end.

Less commonly, a specific KB (Knowledge Base article / patch number) is just buggy or partially installed on your machine, and it breaks every attempt to stack new updates on top of it. Occasionally, DNS issues or network misconfiguration prevent DISM from downloading repair files from Microsoft's servers, leaving the component store in a broken state.

Windows Update Error 0x80073701 Quick Fix

Start here. This is Microsoft's documented first-line workaround and works well when the corruption is minor or caused by old superseded components lingering in the component store.

If that didn't work, don't worry. The next tier of fixes targets deeper corruption that the quick cleanup can't reach.

Intermediate Windows Update Error 0x80073701 Solutions

When component cleanup alone doesn't cut it, you're dealing with actual system file corruption or a stuck update service. These solutions dig deeper and usually resolve the issue.

Advanced Windows Update Error 0x80073701 Fixes

If the intermediate solutions didn't work, the update services themselves might be corrupted or stuck in a bad state. You'll reset them, which forces Windows to rebuild its update cache from scratch.

If you've tried all these steps and Windows Update error 0x80073701 still persists, you're looking at either a hardware problem (failing disk), a network issue preventing downloads, or a seriously corrupted OS state that needs professional recovery. This is where a technician's remote support can save you hours of troubleshooting.

Preventing Windows Update Error 0x80073701

The best fix is avoiding the error altogether. Here's what actually works:

Keep your disk space healthy. Windows Update needs room to stage files before installing them. If your C: drive is below 10 GB free, updates will struggle or fail outright. Regularly clean out old files, move documents to external drives, and use Disk Cleanup or Storage Sense to free space.

Install Servicing Stack Updates regularly. Microsoft pushes these between the main monthly patches. They improve Windows Update reliability and fix issues in the servicing mechanism itself. Don't skip them; they're usually small and install quickly.

Avoid hard power-offs during updates. If an update is running and your PC freezes, don't hold the power button for 10 seconds. Wait at least a minute first; sometimes it's just slow. If it's genuinely stuck, a hard reset will corrupt the component store, and you'll end up chasing errors like 0x80073701 for weeks. Use safe mode or recovery environment instead.

Check your security software and optimisation tools. Third-party antivirus, firewall, or 'PC optimiser' apps sometimes block Windows Update components or delete servicing files thinking they're bloat. Test by temporarily disabling or uninstalling them, then attempting an update. If it works, those tools are the culprit. Contact the vendor for compatibility updates or find an alternative.

If you're on a managed network (WSUS): Ensure your IT department has synchronised updates for your Windows version and approved them for deployment. A misconfigured WSUS server can refuse to serve updates or serve corrupted metadata, triggering error 0x80073701 across multiple PCs.

Run periodic health checks. Every few months, run these three commands as a preventive measure on problem-prone systems:

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

These catch corruption early before it blocks updates. Think of it as a system checkup, like going to the dentist.

See our guide on Windows Update stuck issues for more preventive practices.

Windows Update Error 0x80073701 Summary

Windows Update error 0x80073701 is frustrating but almost always fixable without reinstalling Windows. The error means a required component is missing or corrupt, and you can repair it by cleaning up old components, running system file scans, and rebuilding Windows Update services.

Start with the quick component cleanup, move to DISM and SFC if that fails, then reset your update services or manually install the update. If you've exhausted the advanced fixes and still see error 0x80073701, a network misconfiguration, low disk space, or deep OS corruption is the culprit, and that's where professional support makes sense.

Most importantly, keep your disk space healthy, avoid interrupting updates, and run periodic health checks. These habits prevent Windows Update error 0x80073701 and dozens of other installation failures before they start.