Can't Delete a File? Find What’s Using It with PowerToys

A common reason Windows refuses to delete or rename a file is that another app still has it open. Closing random apps is guesswork, and stopping an unfamiliar process can interrupt unrelated work. Microsoft PowerToys File Locksmith can show which running processes are using a selected file, giving you a way to identify the app before you act.

This guide covers Windows 11 and File Locksmith in PowerToys 0.99.1, released on 29 April 2026 . The steps follow Microsoft’s File Locksmith documentation . We have not independently tested the workflow on a Windows PC.

Close the app normally first

If you know which app has the file open, save your work and close the file from that app. Try the file operation again. If Windows still reports that the file is in use, File Locksmith can help identify the process.

A process is a running app or background component. Ending one can affect more than the single file you are trying to change.

Find which process is using the file

1. Open PowerToys Settings, choose File Locksmith, and turn on Enable File Locksmith.
2. In File Explorer, right-click the exact file. Choose Show more options, then Unlock with File Locksmith.
3. Wait for the scan. The results list processes that are using the selected file. Expand a result to see more information.
4. If you recognise the app, return to it, save any open work, and close the file or app normally. In File Locksmith, choose Reload to refresh the list, then retry deleting or renaming the file.

For example, if you are trying to rename a Word document and the results show Word, save and close that document in Word. Then refresh File Locksmith and try again. The process name is a clue about where to look; it does not tell you whether that app is safe to stop.

Select the specific file when you can. If you select a folder, File Locksmith scans its files and subfolders too, which makes it harder to focus on one item.

If File Locksmith shows no results

First choose Reload in case the process closed while the results were open. A regular scan can miss processes running under a different user account. If you have administrator access, choose Restart as administrator to scan processes that the normal scan could not access. On a work or shared PC, ask the device administrator for help instead of trying to get around its access controls.

A blank list does not prove that nothing is using the file. If an administrator scan still shows no match, read the exact Windows message and avoid ending a process at random.

If the results show more than one process, close the associated apps normally one at a time and refresh after each. This gives you a clear check of whether the file has been released before you stop any process.

Use End task only when you know what will stop

File Locksmith’s End task control terminates the selected process. Save work and close the app normally first; terminating it can discard unsaved changes or interrupt other work handled by the same process. Use End task only when you recognise the process and are ready to stop everything it is doing. Leave unfamiliar Windows services and background processes alone.

For a broader safety checklist, see what to check before ending a Windows background process .

When the error points somewhere else

File Locksmith identifies processes using files. It does not grant account permissions or repair a damaged file. If the message changes to an access-denied or permissions error, investigate the file’s access settings or ask its owner or your administrator.

Close the app that owns the file, refresh File Locksmith, and retry the operation. Reserve End task for a process you can identify and whose remaining work you are ready to stop.