Windows stores update files on your hard drive even after installation — deleting them safely frees up several gigabytes

When Windows installs updates, it keeps a copy of the old system files in a folder called WinSxS (Windows Side-by-Side) and in the Software Distribution folder. These files take up space so you can roll back an update if something breaks, but after a few months of updates, they can consume 5 to 15 gigabytes depending on your system. You can delete them safely once you are confident the updates are working properly.

The safest method uses Windows' built-in Disk Cleanup tool, which only removes files that are genuinely safe to delete. A more aggressive option exists if you want to reclaim more space, but it requires using the command line and carries a small risk if something goes wrong during the process.

Key Takeaways

  • Windows Disk Cleanup is the safest way to remove old update files and requires only a few clicks in Settings.
  • The command line method (DISM) removes more files but should only be used if you are comfortable with the command prompt and have a recent backup.
  • Deleting update cache is safe after updates have been installed and working for at least a week or two.
  • You need administrator access on your computer to delete these files.

Using Disk Cleanup (the safe method)

Open Settings by pressing Windows key + I. Type "Disk Cleanup" in the search box and click the Disk Cleanup app. Windows will ask you to select a drive — choose C: (or whichever drive holds Windows). The scan takes a minute or two.

In the list that appears, look for "Temporary Windows installation files" and "Windows Update Cleanup". Check both boxes. The window shows how much space each will free. Click "Delete Files" and confirm. Windows will remove the files without restarting your computer.

This method is conservative — it only deletes files Windows is certain you do not need. Most people should stop here.

Using DISM for more aggressive cleanup

If Disk Cleanup did not free enough space, you can use the DISM (Deployment Image Servicing and Management) command to remove even older update files. This method is more thorough but also more risky if interrupted. Make sure you have a backup or restore point before starting.

Right-click the Start button and select "Windows Terminal (Admin)" or "Command Prompt (Admin)". Type this command exactly:

DISM.exe /online /Cleanup-Image /StartComponentCleanup /ResetBase

Press Enter and let it run. This can take 10 to 30 minutes depending on how many updates your system has accumulated. Do not close the window or restart your computer while it is running. When it finishes, you will see a message saying the operation completed successfully.

What happens after you delete the cache

Your computer will run normally. Windows will not re-read the old update files unless you manually roll back an update, which is rare. Future updates will still install and work exactly as before.

If you used DISM and something goes wrong with an update later, you cannot roll back to the previous version — you would need to use a backup or restore point. This is why the Disk Cleanup method is safer for most people: it preserves rollback capability while still freeing significant space.

When to delete update cache

Wait at least one to two weeks after a major Windows update before deleting the cache. This gives you time to notice if something is broken and roll back if needed. After that window closes, the old files are safe to remove.

If you are running low on disk space and Windows is warning you, deleting the cache is one of the first things to try. It usually frees more space than clearing temporary files or the recycle bin, and it does not affect how your computer runs.

Checking how much space you freed

Open File Explorer and right-click the C: drive (or whichever drive you cleaned). Select "Properties". The pie chart shows total space used and free space. Compare this to what you saw before cleanup — the difference is what you recovered.

If you want to see the exact size of the WinSxS folder before and after, right-click it (located at C:\Windows\WinSxS), select "Properties", and note the size. After running cleanup, check again to see the reduction.

Frequently Asked Questions

Is it safe to delete Windows Update cache?

Yes, it is safe after updates have been installed and working for a week or two. Windows Disk Cleanup only removes files it knows are safe. The DISM method is also safe but removes your ability to roll back updates, so use it only if you are confident the updates are working properly.

Will my computer run slower after deleting the cache?

No. Deleting old update files does not affect performance. Your computer may actually feel slightly faster if the cleanup freed enough space to reduce disk fragmentation, though the difference is usually small.

Can I delete the cache if I have not restarted since the last update?

It is better to restart first and wait a few days. Some updates require a restart to fully install, and deleting the cache before that completes can cause problems. Restart your computer, let it sit for a week, then clean up.

What if Disk Cleanup does not show the Windows Update option?

Click "Clean up system files" at the bottom of the Disk Cleanup window. This requires administrator access and scans more thoroughly. The Windows Update Cleanup option should appear after the second scan.

Do I need to delete the cache regularly?

No. You can delete it once a year or whenever you run low on disk space. There is no benefit to doing it more often, and it does not hurt to leave the files there if you have plenty of free space.