How to Safely Clean Junk Files in Windows 11

What are junk files in Windows 11?

Junk files are files that Windows and your programs create for short-term use and no longer need: temporary files, the Windows Update download cache, error reports, logs, thumbnail caches and whatever sits in the Recycle Bin. Removing them does not affect how anything works, because Windows recreates what it needs.

Be realistic about the result: cleaning junk frees disk space, but it rarely makes a PC faster on its own. If startup feels slow, look at the programs that launch with Windows as well.

Which files are safe to delete, and which aren't?

How do you clean junk files with Windows 11's own tools?

These steps use only what ships with Windows 11. The Disk Cleanup and DISM steps need an administrator account.

1. See what is using your space

   Open Settings › System › Storage. Windows 11 breaks your drive down into categories such as Installed apps, Temporary files and Documents, so you can see where the space actually went before you delete anything. Cleanup recommendations on the same page lists large or unused files and apps for you to review.

2. Remove temporary files

   In Settings › System › Storage, select Temporary files. Windows scans and lists categories such as Windows Update Cleanup, Temporary files, Thumbnails and Recycle Bin. Tick the ones you want, but leave Downloads unticked unless you have checked that folder yourself, then select Remove files.

3. Turn on Storage Sense

   In Settings › System › Storage, turn on Storage Sense, then open it to set the schedule: how often it runs, and how long files can sit in the Recycle Bin or Downloads before they are removed. Setting Downloads to Never is the safe choice if you keep files there.

4. Run Disk Cleanup with system files

   Press Win, type “Disk Cleanup” and open it. Choose drive C:, then select Clean up system files. This reveals Windows Update Cleanup, Delivery Optimization Files and, after a major upgrade, Previous Windows installation(s). Tick what you want and select OK.

5. Empty the Temp folder by hand

   Press Win + R, type %temp% and press Enter. Select everything with Ctrl + A and press Delete. When Windows says a file is in use, tick Do this for all current items and choose Skip. Those files belong to programs that are running right now.

6. Shrink WinSxS the right way

   Open Terminal as administrator. To see whether a cleanup is worthwhile, run DISM /Online /Cleanup-Image /AnalyzeComponentStore. If it recommends a cleanup, run DISM /Online /Cleanup-Image /StartComponentCleanup and wait for it to finish. Windows removes superseded components safely.

7. Empty the Recycle Bin and review large files

   Right-click the Recycle Bin and select Empty Recycle Bin once you are sure you need nothing in it. Then go back to Cleanup recommendations to review large or unused files. Moving them to an external drive or cloud storage is often better than deleting them.

8. Clear browser caches from the browser itself

   Each browser has its own option for clearing cached images and files, usually in its privacy or history settings. Clearing it from the browser is safer than deleting cache folders while the browser is open, and you can choose to keep passwords and cookies.

Why shouldn't you delete WinSxS, System32 or Prefetch yourself?

Because these folders are part of Windows, not junk. WinSxS, the component store, holds the files Windows uses to install updates, repair itself and turn features on and off. Much of its apparent size comes from hard links to files that also live elsewhere, so it is smaller than it looks. Deleting from it by hand can break updates and system repair.

• System32 contains the core of Windows. Deleting from it can stop Windows from starting.
• C:\Windows\Installer keeps the files Windows needs to repair and uninstall programs. Without them, uninstalls fail later.
• Prefetch helps programs start faster. Windows rebuilds it anyway, so deleting it achieves nothing.

How does CleanSweep clean junk files?

CleanSweep cleans junk only from places known to be safe, shows the size of each category first, and lets you choose what to remove. It never touches your documents, passwords, cookies or settings, never sweeps a risky folder (for example, when %TEMP% has been pointed at the root of a drive), and checks for junctions before deleting each file.

• Free: Windows system junk, including temporary files, the Windows Update cache, Delivery Optimization files, error reports, crash dumps, logs, thumbnail caches and the Recycle Bin.
• Pro: deep cleanup of browser caches (Chrome, Edge, Brave, Vivaldi, Opera, Firefox), app caches (Discord, VS Code, Slack, Teams, Spotify, Steam), privacy traces and developer caches, plus an automatic weekly cleanup. Pro also shrinks WinSxS using Windows' own DISM, as part of system-wide leftover repair.

See junk cleanup in CleanSweep. The free edition is free forever with no ads. Pro is a one-time US$14.99 for 3 PCs, and you can try it free for 7 days in the app.

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