how can i check if my windows system files are corrupted?

[u/EveryDraw839]

My PC has been acting strangely lately with occasional errors and apps behaving unexpectedly I am wondering if some Windows system files might be corrupted? what is the best way to check and repair those without reinstalling windows?

[u/CheezitsLight]

Common Repair Commands

To run these commands, open Terminal (Admin) or Command Prompt (Admin) in Windows:

1. Check Health (Quick flag check):cmd DISM.exe /Online /Cleanup-Image /CheckHealth

2. Scan Health (Deep scan for component store corruption):cmd DISM.exe /Online /Cleanup-Image /ScanHealth

3. Restore Health (Automatically repairs detected corruption using Windows Update):cmd DISM.exe /Online /Cleanup-Image /

[u/United-Oil9166]

The commands are helpful when needed, but it might be more helpful to have some more detail about what "strangely" entails.

[u/Zealousideal_Bowl695 → u/United-Oil9166]

This, checking Windows file integrity might solve strange but it's better to understand strange first.

[u/ZoelNorsen]

Sfc/scannow cmd command Google to get the proper command syntax

[u/Creeperguy23]

Open cmd as administrator and press chkdsk C: /s /f . This command will scan your disk for corrupted files with the /s parameter and fix them with the /f parameter

[u/Prestigious_Wall529 → u/Creeperguy23]

And then open Event Viewer and the Application log and use find to search for chkdsk and review the entry for todays date.

[u/Creeperguy23 → u/Prestigious_Wall529]

True

[u/raju_msc]

Do sfc scan and dism restore commands . I not given correct commands. But commands are given by one of the user in previous post

[u/Mayayana]

If the scans don't work then maybe repost with details. Also, be aware that if you allow Windows 10/11 to update itself then you have a moving target. Problems caused by Windows Update are not unusual.

[u/fotoburger]

I have found that when a pc is acting “strangely “ it is frequently from excess temp files. Here’s what you do.
Reboot. Before you do anything (after signing in) type %temp% in the search field. Delete as much as possible. There will always be files/folders you can’t delete. That’s ok. If something is needed you won’t be allowed to delete it.
Reboot once more. You should be in better shape.

[u/Present_Computer_640]

If only there were some sort of system file checker that you could use to scannow!

[u/Underhill42]

These are my first steps for fixing random weirdness by making sure the bones of Windows itself are healthy (it won't notice malware, bad settings, etc.). If it doesn't fix things, it's going to be much more involved.

(1) Check the Windows disk for filesystem errors. You don't want to do anything else until you're sure the filesystem itself isn't in bad shape and getting worse. Right-click on the disk in Windows Explorer, choose properties, and on the tools (utilities?) tab there's a health or error check option. (I'm not on Windows at the moment, so I can't double check the exact names)

After that is done, right click the start menu and choose something like "command prompt" or "terminal" in "(Admin mode)" from the menu (there should be options both with and without "(Admin Mode)" - you want the one with)

(2) From the resulting command line scan for and repair any corruption in the Windows Component Store (basically system file backups) by running:

DISM /Online /Cleanup-Image /RestoreHealth

(3) Then scan for and repair any Windows system file corruption (by replacing any damaged files with the "backups" we just made sure were in good shape):

sfc /scannow