SpaceSentinel

Is WinSxS Safe to Delete? The Right Way to Shrink It

Never delete it directly, but you can compress it safely. WinSxS holds every version of Windows components (update rollback depends on it). Microsoft's official slimming command is the DISM component cleanup.

  1. Open an elevated terminal (Win+X → Terminal (Admin))
  2. Run: Dism /Online /Cleanup-Image /StartComponentCleanup (10-20 minutes; removes components superseded by newer versions)
  3. For a deeper clean add /ResetBase (warning: installed Windows updates can no longer be uninstalled afterwards — only recommended on systems that have been stable for months)
  4. If it fails with error 0x80070005 (access denied): most of the cleanup has usually already happened — reboot and run it once more to finish
  5. Also: WinSxS looks bigger than it really is — much of it is hard links to files elsewhere in the system, so its true exclusive size is smaller than reported
Download the free open-source Windows cleaner

FAQ

Why is WinSxS so large?

It stores multiple versions of every Windows component to support updates and rollback. It grows with every update; 10-15GB is normal.

Are third-party WinSxS cleaners safe?

Not recommended. DISM is the only Microsoft-supported method; brute-force deletion can corrupt the component store and break Windows Update permanently.